Interstate 91
Interstate 91 (I-91) is a north–south Interstate Highway spanning 290 miles (470 km) through the New England states of Connecticut, Massachusetts, and Vermont. Its southern terminus lies at Interstate 95 in New Haven, Connecticut, while its northern terminus reaches the Canada–United States border in Derby Line, Vermont, connecting directly to Quebec's Autoroute 55. The highway largely parallels the Connecticut River along its eastern bank, replacing U.S. Route 5 as the principal north-south corridor through the valley and linking urban centers including Hartford, Connecticut, and Springfield, Massachusetts, with rural areas in Vermont's Northeast Kingdom.[1][2][3]
Construction of I-91 began in the late 1950s as part of the broader Interstate Highway System, with the first segment in Vermont opening in 1958 and full completion spanning into the early 1980s, transforming regional connectivity by facilitating faster travel and economic exchange.[4] The route supports significant freight movement to and from Canada, underscoring its role in trade, though its urban segments have drawn criticism for dividing neighborhoods during building, as seen in Springfield where it disrupted established communities.[1][5]
Route description
Connecticut
Interstate 91 begins in Connecticut at its interchange with Interstate 95 in New Haven, marking the southern end of its 58-mile segment through the state.[6] The highway proceeds north as a six-lane freeway through urban New Haven, providing access via Exit 1 to Route 34 west toward downtown and Exit 2 to Route 15 north (Wilbur Cross Parkway) and state facilities.[7] North of New Haven, I-91 enters North Haven and continues through Wallingford and Cheshire, serving suburban commuters with exits for local routes like US 5 and Route 68. In Meriden, it intersects Interstate 691 eastbound (Exit 21) and the Wilbur Cross Parkway (Route 15), forming a critical junction for traffic from the Naugatuck Valley heading toward Hartford.[7] Further north, I-91 passes through Cromwell and Rocky Hill, crossing the Connecticut River via the William H. Putnam Memorial Bridge (carrying Route 3) near Wethersfield before entering Hartford. In Hartford, the highway crosses the Connecticut River again on the Founders Bridge northbound, linking the city's west side to East Hartford. Immediately north, it reaches the Mixmaster interchange (Exits 29–32), a complex stack interchange with Interstate 84 that facilitates east-west travel to Waterbury and Boston while handling heavy commuter and freight volumes.[8] Annual average daily traffic (AADT) on I-91 through Hartford exceeds 152,000 vehicles, underscoring its role as a primary north-south artery for the capital region.[9] North of the Mixmaster, Exit 34 connects to Interstate 291 east, providing a bypass around downtown Springfield, Massachusetts. Beyond Hartford, I-91 traverses Windsor and Windsor Locks, with Exit 40 linking to the Bradley International Airport Connector (Route 20). The route then continues through rural areas in Suffield and Enfield, featuring exits for US 5 and Route 159, before reaching the Massachusetts border near milepost 58. Throughout its Connecticut length, I-91 supports regional freight movement, including over 10,000 trucks daily north of Hartford, channeling goods from New Haven's port northward via connections to I-95 and rail hubs.[10] The freeway maintains four to six lanes, with urban sections elevated to navigate dense development and river crossings.
Massachusetts
Interstate 91 enters Massachusetts from Connecticut in the town of Longmeadow at milepost 0, designated as Exit 1 for Massachusetts Route 83, and proceeds northward for 54.99 miles to the Vermont state line in Bernardston.[11] The highway closely parallels the Connecticut River, staying within a few miles of its eastern bank through the densely populated Pioneer Valley region, passing major cities including Springfield, Holyoke, Northampton, and Greenfield.[12] This corridor interfaces with historic industrial zones, such as former manufacturing districts in Springfield and Holyoke, where the route's alignment reflects mid-20th-century planning to link riverfront access with urban centers.[13] In the Springfield metropolitan area, I-91 features an elevated viaduct spanning approximately 2 miles through downtown, carrying northbound and southbound traffic on a 4,200-foot, 48-span structure that elevates the roadway above local streets and the river valley.[14] [15] Key interchanges include Exit 2 for the southern terminus of Interstate 291, which provides a partial beltway connection eastward toward the Massachusetts Turnpike; Exit 12 for Interstate 391, a spur route extending to Chicopee and Holyoke; and Exit 14 for Interstate 90 (Massachusetts Turnpike) in West Springfield, facilitating east-west travel across the state.[16] North of Springfield, the highway transitions through more suburban and rural terrain near Northampton (Exits 18–20) and Greenfield (Exits 26–28), with interchanges serving local routes like U.S. Route 5 and Massachusetts Route 2.[17] Traffic volumes peak at around 110,000 vehicles per day through Springfield's urban core, reflecting heavy commuter flows between the Pioneer Valley's employment hubs and Hartford, Connecticut, to the south, before tapering to 25,000–35,000 vehicles per day north of Northampton toward the Vermont border.[11] [13] The route's four-lane configuration supports freight movement tied to regional logistics along the river valley, with average daily traffic declining northward as population density decreases.[11]Vermont
Interstate 91 enters Vermont from Massachusetts at the town of Guilford, immediately north of the state line, and proceeds northward through Brattleboro as a four-lane divided highway paralleling the Connecticut River and U.S. Route 5.[18] The route's initial exits in Vermont—numbered starting from Exit 1—serve Brattleboro and nearby communities, with Exit 1 at mile 7 providing access to U.S. 5 and local services.[19] From Brattleboro, I-91 continues through rural eastern Vermont, passing exits for towns such as Dummerston (Exit 4 at mile 18) and Westminster (Exit 5 at mile 28), maintaining two lanes in each direction throughout its 177-mile length in the state.[19][18] North of Hartford, I-91 reaches White River Junction at Exit 11 (mile approximately 70), where it intersects Interstate 89, facilitating connections westward to Montpelier and Burlington.[20] The highway then traverses the Upper Connecticut River Valley, offering scenic views and access to small towns like St. Johnsbury (near Exit 19) and Lyndonville, before entering the Northeast Kingdom region.[18] In this northern stretch, exits such as those near Newport (Exit 27) support local agriculture and outdoor recreation, including proximity to ski areas like Burke Mountain via connecting routes.[19] Traffic volumes remain relatively low compared to southern segments, reflecting the rural character and limited urban development along the corridor.[21] I-91 terminates at Derby Line near Exit 29 (mile 177), directly adjoining the Canada–U.S. border, where it seamlessly connects to Quebec Autoroute 55, enabling efficient cross-border trade and travel between Vermont and the Eastern Townships of Quebec.[19][3] This international linkage, combined with the route's alignment through Vermont's scenic river valley, plays a key role in supporting tourism by providing primary access for visitors from southern New England and New Hampshire to Quebec destinations, as well as facilitating regional economic exchanges with lower daily vehicle counts dominated by seasonal and freight movements.[22][23]
History
Planning and designation
The corridor for Interstate 91 evolved from early 20th-century efforts to establish reliable north-south travel in western New England, primarily along the path of U.S. Route 5, commissioned in 1926 to connect Canada with southern New England via the Connecticut River valley. This route built upon the New England Interstate Route 2, marked in 1922 as part of a regional numbering system coordinated by the six New England states to standardize signage and improve cross-border travel on existing roads.[24] Upgrades to U.S. Route 5 in the 1920s and 1930s addressed chronic issues like muddy surfaces and narrow widths, with federal aid under programs like the Federal Highway Act of 1921 facilitating pavement and widening to handle growing automobile traffic.[24] New Deal initiatives in the 1930s further enhanced connectivity along this corridor through public works projects, including resurfacing and bridge reinforcements funded by the Works Progress Administration and related federal programs, which prioritized economic stimulus via infrastructure in rural and valley areas. These efforts underscored the strategic value of a continuous north-south artery for freight from Canadian ports to U.S. industrial centers, though they stopped short of limited-access design due to cost constraints and technological limits of the era.[25] Post-World War II planning accelerated with the Federal-Aid Highway Act of 1944, which authorized designation of a 40,000-mile National System of Interstate Highways, including preliminary alignments for New England routes paralleling U.S. 5.[26] The 1956 Federal-Aid Highway Act formalized federal funding at 90% of costs, prompting detailed route selection for what became I-91, with debates among state engineers favoring the Connecticut River valley over inland alternatives through the Berkshires or Green Mountains, as the valley offered flatter gradients, fewer elevation changes, and proximity to existing population and rail corridors for lower construction costs and higher utility.[26][13] Officials from Connecticut, Massachusetts, and Vermont highway departments, in coordination with the federal Bureau of Public Roads in Washington, D.C., finalized the designation around 1957, emphasizing bypasses around smaller towns where feasible while integrating with urban gateways like Hartford and Springfield to support regional commerce without excessive deviation. This consensus reflected empirical assessments of traffic forecasts and topography, prioritizing causal efficiency in linking the Northeast to Quebec over politically driven reroutes that risked higher expenses or environmental hurdles.[27]Construction phases
Construction of Interstate 91 occurred primarily between the late 1950s and early 1970s, aligned with the federal Interstate Highway System established by the 1956 Federal-Aid Highway Act, which provided 90% funding for qualifying projects nationwide. The highway's build-out prioritized southern segments first, progressing northward through Connecticut, Massachusetts, and Vermont, with engineering focused on bridging the Connecticut River and navigating urban constraints without extensive tunneling.[28] In Connecticut, precursor limited-access highways laid groundwork, but designated I-91 segments opened in the mid-1960s. The 11-mile section from Meriden (near present I-691) to Rocky Hill opened on October 27, 1965, enabling non-stop travel from Hartford northward.[6] This was followed by the 18.8-mile stretch from New Haven (at I-95) to Meriden on January 7, 1966, completing the southern core route amid challenges like integrating with the Connecticut River crossings via existing bridges such as the Charter Oak.[6] [29] Earlier alignments, including from Windsor Locks to Enfield in 1959, facilitated connectivity but required upgrades to Interstate standards.[6] Massachusetts construction advanced in parallel, with initial rural sections opening in 1960, including 6.8 miles from the Vermont border south of Bernardston-Greenfield and 4.1 miles from the Connecticut border to Exit 3 in Springfield.[13] Further openings followed: 1.2 miles near Springfield in 1964, 8.5 miles linking Northampton to Whately-Greenfield in 1965, and 15.1 miles from Exit 14 to 21 in 1966.[13] The most complex urban phase, featuring elevated viaducts over the Connecticut River and downtown Springfield to avoid floodplain tunneling and minimize displacement, concluded in 1970 with the final 6.3 miles through Chicopee and West Springfield.[13] [30] Vermont's phases began earliest in the south, with construction starting near Guilford in 1957 and the initial 5.9-mile segment from the Massachusetts line to Vernon opening November 1, 1958.[4] [31] Northern extensions progressed through the 1960s, addressing rugged terrain and multiple river spans, with full designation to the Canadian border achieved by the mid-1970s, though some connectors finalized later.[32] Rural alignments often repurposed former rail corridors, reducing acquisition needs while ensuring four-lane divided standards.[33]Unbuilt extensions and proposals
In the mid-1960s, federal and state planners proposed extending Interstate 91 southward from its planned terminus at the Interstate 95 interchange in New Haven, Connecticut, across Long Island Sound to Shoreham in Suffolk County, New York, via a 19.3-mile, four-lane Shoreham-New Haven Bridge featuring a 1,500-foot main span and 135-foot vertical clearance.[34][35] The extension would have linked to Interstate 91 in East Haven, Connecticut, and connected on the New York side to an upgraded William Floyd Parkway (Suffolk County Route 46), integrating with the Long Island Expressway (Interstate 495) to facilitate freight and commuter traffic bypassing New York City congestion.[35][36] Initial cost estimates in 1971 pegged the project at $565 million, but by 1979 they had risen to $1.4 billion amid inflation and design refinements, with later 2016 assessments exceeding $15 billion for a bridge variant or $30 billion for a tunnel alternative.[35] Traffic forecasts from 1990 projected only 15,500 vehicles per day, with peak-hour volumes of 3,000 to 5,000, insufficient to justify the investment relative to existing ferry and circumferential routes around the Sound.[35] The proposal faced strong opposition from Connecticut officials, including Governor Ella Grasso and U.S. Senator Abraham Ribicoff, who argued it would degrade coastal quality of life, harm fisheries, and disrupt bird migration patterns without commensurate economic gains, despite a 1968 Wilbur Smith Associates study estimating 40,000 new jobs in Suffolk County and 15,000 in Connecticut.[35] Benefit-cost analyses highlighted poor returns, factoring in high construction expenses, environmental mitigation requirements under emerging federal laws like the National Environmental Policy Act of 1969, and limited regional demand, leading to its abandonment by the late 1970s.[35][34] The idea resurfaced sporadically in the 1990s and 2016 tied to air cargo development at former naval sites but was repeatedly shelved for similar empirical shortcomings.[35]Impacts and effects
Economic and transportation benefits
Interstate 91 serves as a critical north-south artery for freight transport, carrying an average of over 10,000 trucks per day north of Hartford, Connecticut, up to the state line with Massachusetts, thereby streamlining the movement of goods from southern ports like New Haven northward to the Canadian border via seamless connection to Quebec Autoroute 55.[10] This high-volume truck traffic, which constitutes a significant portion of interstate freight (approximately 80% nationally), enhances supply chain efficiency and reduces delivery costs for industries reliant on just-in-time logistics.[37] By supplanting slower, two-lane predecessors such as U.S. Route 5, I-91 has cut travel times substantially—enabling, for instance, more reliable multi-state hauls that support manufacturing and distribution hubs in Hartford and Springfield, Massachusetts.[28] The highway's infrastructure has driven job creation through construction and maintenance, with projects like the $500 million reconfiguration of the I-91/I-691/Route 15 interchange in Meriden, Connecticut—initiated in phases from 2024 onward—incorporating project labor agreements that provide workforce development and good-paying union jobs for local trades.[38] Similarly, a $125 million federal grant for phase three of this effort in 2024 has further amplified employment in engineering, demolition, and bridgework, contributing to regional economic multipliers in construction-related sectors.[39] These investments sustain logistics employment by maintaining corridor reliability, where I-91's role as a primary trucking route bolsters warehousing and distribution activities amid growing e-commerce demands. In Vermont, I-91 facilitates tourism-driven growth by providing direct access to recreational destinations, with southbound traffic volumes on the highway serving as a key proxy for visitor inflows that generate seasonal revenue spikes in hospitality and outdoor sectors. Communities along the route, such as Springfield, leverage exit proximity for commerce, positioning the area as a regional hub that benefits from interstate-enabled retail and service expansion.[40] Overall, I-91's connectivity has spurred commercial development in adjacent towns, as evidenced by economic promotion strategies highlighting its role in attracting businesses through improved market access and reduced isolation.[41]Urban and social transformations
The construction of Interstate 91 through Springfield, Massachusetts, in the 1960s and 1970s physically divided the North End neighborhood from the Connecticut River waterfront and downtown areas, exacerbating pre-existing isolation from earlier infrastructure like railroads and urban renewal projects.[42][43] This severance contributed to a measurable decline in the neighborhood's vitality, including reduced walkability and community cohesion, though broader factors such as industrial shifts also played roles in urban decay patterns already evident by the 1950s.[44] In Hartford, Connecticut, I-91's alignment, combined with Interstate 84, bisected the city and isolated sections of the North End, such as the Clay Arsenal area, where poverty rates remain among the highest in Connecticut's major cities as of 2023.[45][46] Eminent domain acquisitions for I-91 displaced residents across its route, with 340 properties seized in Vermont's Windham County alone during construction, fragmenting communities and farmland.[32] These displacements affected diverse populations, but the highway's radial design lowered commuting barriers, accelerating suburban settlement patterns in areas like West Springfield and Enfield, where populations grew post-1960s as urban cores depopulated. Empirical studies indicate radial highways like I-91 explained about half of central city population declines between 1950 and 1990, intensifying de-urbanization driven by white responses to black in-migration rather than originating it.[47][48] While neighborhood divisions persisted, I-91 enhanced regional connectivity, enabling cross-state access that mitigated some isolation effects; for instance, Springfield's overall population decline from 175,000 in 1970 to 152,000 by 2000 was less severe than in comparable Rust Belt cities, partly due to metro-area integration facilitated by the highway.[49] In Vermont, routing avoided major downtowns, limiting urban blight but still splitting rural settlements, with social cohesion maintained through preserved village cores.[31] These transformations reflect highways amplifying preexisting demographic and economic pressures rather than solely causing them, as evidenced by pre-interstate suburban trends in New England.[50]Environmental and land acquisition issues
The construction of Interstate 91 involved extensive land acquisition through eminent domain, particularly in urban segments of Connecticut, where state authorities demolished hundreds of buildings in areas such as New Haven's Wooster Square and Mill River neighborhoods to secure right-of-way during the 1960s.[51][52][53] Similar takings occurred in Hartford and other corridor cities, aligning with federal interstate funding that prioritized rapid buildout over pre-NEPA (1969) environmental scrutiny, resulting in fragmented parcels along the 58-mile Connecticut stretch alone.[54] Ecologically, I-91's routing parallel to the Connecticut River valley has induced habitat fragmentation by bisecting riparian and forested areas, compounding prior disruptions from 19th-century railroads and promoting exurban sprawl across approximately 323,000 acres projected for density shifts by 2020 in the watershed.[55] This linear barrier impedes wildlife movement and alters hydrologic patterns in floodplains, with general road ecology data indicating that highways of I-91's scale (typically 200-300 feet wide) effectively sterilize 2-4 acres of contiguous habitat per mile through direct clearing and edge effects.[56][57] Traffic-related emissions from I-91, including nitrogen oxides and particulates, elevated local air pollution concentrations during early operations in the pre-Clean Air Act era (pre-1970), when uncontrolled vehicles contributed to regional smog precursors without modern catalytic converters or fuel standards.[58] However, by diverting freight and through-traffic from congested local roads to higher-speed limited access, the interstate facilitated overall emissions reductions per ton-mile hauled, as evidenced by post-1970 fleet turnover yielding up to 99% cuts in criteria pollutants from new vehicles, despite localized hotspots near interchanges.[59][58] Routing debates, such as those delaying Springfield, Massachusetts completion until 1971 due to urban impacts, highlighted early concerns over such trade-offs, though federal priorities emphasized connectivity's logistical efficiencies over isolated ecological costs.[28]Infrastructure and operations
Design characteristics
Interstate 91 adheres to standard Interstate Highway System geometric criteria, featuring a divided freeway with two 12-foot travel lanes in each direction and minimum paved shoulder widths of 10 feet outside and 4 feet inside to accommodate emergency and maintenance operations.[60] This cross-section supports high-volume traffic flow while providing lateral clearance for safety, though urban segments occasionally incorporate narrower shoulders or auxiliary lanes to fit constrained rights-of-way. The design emphasizes vehicular mobility, with limited provisions for pedestrian or cyclist accommodations, reflecting the era's focus on automobile-centric infrastructure over multimodal connectivity. In urban corridors like Hartford, Connecticut, and Springfield, Massachusetts, the route employs elevated viaducts to traverse rail yards, industrial zones, and floodplains without extensive ground disruption, as exemplified by the 1,800-foot Dutch Point Viaduct in Hartford spanning multiple rail lines.[61] [59] These structures prioritize capacity and separation from local traffic but result in visual and acoustic barriers between city centers and the adjacent Connecticut River. Rural portions, especially in Vermont, maintain flatter alignments and higher design speeds approaching 70 mph, suited to the valley's relatively level terrain.[60] Crossings of the Connecticut River utilize multi-span girder bridges engineered for the waterway's moderate spans and seasonal flooding, such as the structure in Chicopee, Massachusetts, which facilitates seamless north-south continuity without vertical navigation clearances beyond vehicular needs.[62] The absence of tunnels underscores a cost-effective adaptation to the region's geology and hydrology, favoring embankments and short-span overpasses where terrain demands, thereby minimizing construction complexity while ensuring reliable all-weather access.[60]Maintenance and rehabilitation projects
The Massachusetts Department of Transportation (MassDOT) conducted the Interstate 91 Viaduct Study from 2018 to 2019, evaluating the 2.5-mile elevated viaduct section in Springfield built in the late 1960s, which had experienced substantial deterioration including structural fatigue and corrosion.[59][63] The study assessed rehabilitation options such as retrofitting existing structures versus full replacement, incorporating cost-benefit analyses that weighed lifecycle costs, traffic disruption, and seismic resilience, ultimately recommending preservation with targeted upgrades over demolition to minimize expenses estimated in the hundreds of millions.[59] Concurrently, MassDOT completed a major viaduct rehabilitation in 2018, including bridge deck resurfacing, joint replacements, and painting to extend service life amid ongoing interstate maintenance contracts for guardrail and pavement work along I-91 from the Connecticut state line northward.[28][64] In Connecticut, the Department of Transportation (CTDOT) initiated the Dutch Point Viaduct rehabilitation project on I-91 southbound in Hartford in March 2025, focusing on substructure repairs, bearing refurbishments, and concrete deck overlays to address age-related wear on the structure carrying traffic over local roads.[65] Safety-driven realignments include the relocation of I-91 northbound Exit 29 in Hartford, with construction starting in spring 2023 to alleviate congestion and operational failures at the interchange, funded through state and federal partnerships.[66] Broader proposals under the CityLink East initiative, detailed in CTDOT's December 2023 final report, advocate relocating the I-84/I-91 interchange northward, constructing a new Connecticut River crossing, and streamlining ramps to reduce accident risks from complex weaving patterns, with preliminary cost estimates exceeding $1 billion supported by federal infrastructure grants.[67][68] Interchange upgrades at I-91/I-691/Route 15 in Meriden, ongoing since early 2023, incorporate bridge repairs, lane additions, and ramp realignments, with Phase 3 funded by a $125 million federal award in October 2024 under an 80% federal-20% state split typical for such resilience enhancements against flooding and wear.[38][69] Additional bridge replacements over I-91 in Wallingford, slated for 2028-2030 at $60-90 million, target structurally deficient spans with federal funding covering 80% to improve load capacity and seismic standards.[70] Vermont Agency of Transportation (VTrans) efforts emphasize bridge rehabilitations due to general deterioration, as seen in the 2014 study for parallel I-91 northbound and southbound bridges (Nos. 24N and 24S), which recommended substructure strengthening and deck resurfacing to maintain adequacy for interstate loads.[71] The Westminster I-91 bridges (No. 21N&S) underwent evaluation in a 2014 engineering study, leading to rehabilitation options prioritizing preservation over replacement to address corrosion and fatigue, with work contracted for structural enhancements.[72] A Connecticut River bridge on I-91, closed in April 2023 after inspections revealed poor condition and a reduced 15-ton weight limit, is scheduled for reopening post-rehabilitation to restore full capacity, reflecting routine federal-mandated inspections integrated with weather-resilience upgrades across the corridor.[73] Federal Highway Administration (FHWA) and state partnerships provide ongoing funding for I-91 resurfacing and inspections, such as 80/20 matching grants for pavement overlays and flood mitigation, ensuring compliance with national bridge standards amid increasing demands from freight traffic and climate events.[69][70] These projects collectively prioritize cost-effective retrofits, with lifecycle analyses favoring rehabilitation over full rebuilds where feasible, though major interchanges require extensive federal investment to sustain safety and throughput.[59]Exit list
Connecticut exits
| Exit | Destinations | Notes |
|---|---|---|
| 1 | I-95 (Connecticut Turnpike) – New Haven, New York City, Boston | Southern terminus of I-91. |
| 2A | York Street – New Haven | |
| 2B | US 5 – New Haven | |
| 3 | Humphrey Street – New Haven | |
| 4 | Chapel Street / Church Street / Olive Street – New Haven | |
| 5 | State Street / Trumbull Street (US 5) – New Haven | |
| 6 | Willow Street – New Haven | |
| 7 | Russell Street (US 5) – New Haven | |
| 8 | Middletown Avenue (CT 17) – New Haven, Hamden, Foxon Road | |
| 9 | US 5 – Hamden | |
| 10 | CT 15 (Wilbur Cross Parkway) – Hamden, Meriden | |
| 11 | CT 40 (Mount Carmel Connector) – Hamden | |
| 12 | US 5 / CT 22 (Washington Avenue) – North Haven | |
| 13 | US 5 (South Colony Road) – Wallingford | |
| 14 | CT 150 (Woodhouse Avenue / North Elm Street) – Wallingford | |
| 15 | CT 68 – Wallingford | |
| 16 | CT 17 – Meriden | |
| 17 | CT 71 – Meriden | |
| 18 | I-691 east – Meriden, Middletown | Eastern terminus of I-691. |
| 19 | CT 156 / CT 157 – Middletown | |
| 20 | CT 66 – Middletown | |
| 21 | CT 372 (Berlin Road) – Berlin, New Britain | |
| 22 | CT 3 – Cromwell | |
| 23 | CT 9 – Cromwell, Middletown | |
| 24 | CT 99 – Rocky Hill | |
| 25 | CT 3 – Wethersfield | |
| 26 | CT 4 – Wethersfield | |
| 27 | CT 229 – Hartford | |
| 28 | CT 2 – Hartford | |
| 29 | US 5 (Whitehead Highway / Brainard Road) – Hartford | Split into 29A (Whitehead Highway) and 29B (US 5). |
| 30 | US 5 – Hartford | |
| 31 | CT 175 – Hartford | |
| 32 | I-84 – Hartford, Waterbury, Danbury, Boston, New York City | Major east-west connection; split into 32A (east) and 32B (west/Trumbull Street). |
| 33 | Wethersfield Avenue – Hartford | |
| 34 | Meadow Road – Windsor | |
| 35 | CT 218 (Putnam Highway) / I-291 east – Windsor, South Windsor | Connection to I-291; split into 35A (I-291) and 35B (CT 218). |
| 36 | CT 178 (Park Avenue) – Windsor | |
| 37 | CT 305 (Bloomfield Avenue) – Windsor | |
| 38 | CT 75 (Poquonock Avenue) – Windsor Locks | Split in some configurations. |
| 39 | CT 305 – Windsor Locks | |
| 40 | CT 20 (Bradley International Airport Connector) – Windsor Locks, Bradley International Airport | Primary access to Bradley International Airport. |
| 41 | Center Street / CT 75 – Suffield | |
| 42 | CT 159 (South Main Street) – Suffield | |
| 43 | CT 159 – Thompsonville (Enfield) | |
| 44 | CT 159 – Thompsonville (Enfield) | |
| 45 | CT 20 – Warehouse Point (Enfield) | |
| 46 | CT 191 – Scitico (Enfield) | |
| 47 | CT 190 (Hazard Avenue) – Enfield | Split into 47E (east) and 47W (west). |
| 48 | CT 220 (Elm Street) – Enfield | |
| 49 | US 5 (Enfield Street) – Enfield | Northernmost exit in Connecticut before Massachusetts state line. |
Massachusetts exits
Interstate 91 traverses 55 miles through Massachusetts, entering from Connecticut near Longmeadow and exiting to Vermont near Guilford, with mile-based exit numbering implemented statewide between March 3 and March 18, 2021, starting from mile 0 at the southern state line.[76][77] The southern segment features closely spaced exits serving the urban Springfield metropolitan area, where the highway runs on an elevated viaduct, providing multiple access points for commuters and freight to industrial zones along the Connecticut River; northern exits shift to more rural service with wider spacing.[76] Key interchanges include Exit 11 to I-90 (Massachusetts Turnpike) for regional travel and Exit 9 to I-391 for Holyoke access, emphasizing the route's role in linking urban hubs to the Pioneer Valley.[76]| Exit | Destinations |
|---|---|
| 2 | Massachusetts Route 83 south – Forest Park, East Longmeadow[76] |
| 3 | US 5 / Massachusetts Route 57 – Springfield[76] |
| 4 | Massachusetts Route 83 south / Main Street (southbound); Broad Street / Main Street (northbound) – Springfield[76] |
| 5 | East Columbus Avenue (northbound); West Columbus Avenue (southbound as 5B) – Springfield[76] |
| 6 | I-291 east / US 20 – Springfield, Chicopee[76] |
| 7A/B | US 20 west / Massachusetts Route 20A east – Springfield (northbound)[76] |
| 8 | Massachusetts Route 116 (northbound); US 20 / Massachusetts Route 116 (southbound) – West Springfield[76] |
| 9 | I-391 north – Chicopee, Holyoke[76] |
| 10A/B | US 5 – Chicopee, Holyoke[76] |
| 11 | I-90 (Massachusetts Turnpike) / US 5 – West Springfield[76] |
| 12 | Lower Westfield Road – West Springfield[76] |
| 14 | US 202 – Holyoke[76] |
| 15A/B | Massachusetts Route 141 (northbound); southbound to Route 141[76] |
| 23 | US 5 – Holyoke, South Hadley[76] |
| 25 | Massachusetts Route 9 – Northampton (northbound)[76] |
| 26 | US 5 / Massachusetts Route 10 (southbound) – Northampton[76] |
| 27 | US 5 / Massachusetts Route 10 – Hatfield[76] |
| 30 | US 5 / Massachusetts Route 10 (northbound) – Hatfield[76] |
| 32 | US 5 / Massachusetts Route 10 (southbound) – Hatfield, Amherst[76] |
| 35 | US 5 / Massachusetts Route 10 – Amherst, Hadley[76] |
| 36 | Massachusetts Route 116 (southbound) – Amherst[76] |
| 43 | Massachusetts Routes 2 / 2A – Erving, Greenfield[76] |
| 46 | Massachusetts Route 2 – Greenfield[76] |
| 50A/B | Massachusetts Route 10 (northbound); to Route 10 (southbound) – Bernardston[76] |
Vermont exits
Interstate 91 enters Vermont from Massachusetts and traverses 177 miles northward through the state, primarily paralleling the Connecticut River before veering east toward the Canadian border at Derby Line. Exits are numbered sequentially from 1 to 29, serving communities in Windham, Windsor, Orange, Caledonia, and Orleans counties. The following table lists the exits from south to north, including approximate mileposts from the southern state line.[19]| Exit | mi | Locations |
|---|---|---|
| 1 | 7 | Brattleboro |
| 2 | 9 | Brattleboro |
| 3 | 11 | Brattleboro |
| 4 | 18 | Dummerston |
| 5 | 28 | Westminster |
| 6 | 35 | Rockingham |
| 7 | 41 | Springfield |
| 8 | 51 | Ascutney |
| 9 | 60 | Hartland |
| 10 | 69 | White River Junction |
| 11 | 70 | Hartford |
| 12 | 72 | Wilder |
| 13 | 74 | Norwich |
| 14 | 84 | Thetford |
| 15 | 91 | Fairlee |
| 16 | 97 | Bradford |
| 17 | 110 | Wells River |
| 18 | 120 | Barnet |
| 19 | 128 | Waterford |
| 20 | 128 | St. Johnsbury |
| 21 | 130 | St. Johnsbury |
| 22 | 132 | St. Johnsbury |
| 23 | 137 | Lyndonville |
| 24 | 140 | Lyndon |
| 25 | 155 | Barton |
| 26 | 161 | Orleans |
| 27 | 170 | Newport |
| 28 | 172 | Derby |
| 29 | 177 | Derby Line |