I-93

I-93
Country	USA
Route	93
Type	Interstate
Length mi	189.95
Established	1957
Direction a	South
Terminus a	Boston
Direction b	North
Terminus b	St. Johnsbury, Vermont

I-93 Interstate 93 is a primary Interstate Highway in the northeastern United States connecting Boston, Massachusetts with northern New Hampshire and central Vermont. The route serves as a principal arterial for metropolitan Boston, the Merrimack Valley, the White Mountains region, and the Connecticut River valley, linking urban centers, tourist destinations, and transportation hubs. It intersects major east–west corridors and provides access to notable institutions, parks, and airports along its corridor.

Route description

The southern terminus near Kendall Square in Cambridge, Massachusetts begins amid the dense urban fabric of Boston and Cambridge, passing landmarks such as Fenway Park, Boston Common, and Logan International Airport via connecting routes. Moving northward, the route traverses the Greater Boston area and the Merrimack River corridor, serving suburban centers including Medford, Massachusetts, Woburn, Massachusetts, and Andover, Massachusetts before reaching industrial and commercial nodes near Lowell, Massachusetts and Lawrence, Massachusetts. Continuing into New Hampshire, the highway follows the Merrimack River through Nashua, New Hampshire and Manchester, New Hampshire, providing access to Dover, New Hampshire via connecting routes. The alignment turns northwest to climb toward the White Mountains, skirting resort towns such as Conway, New Hampshire and North Conway, New Hampshire, and providing connections to Mount Washington attractions. The northern section enters Vermont near the Connecticut River valley, terminating in the vicinity of St. Johnsbury, Vermont where connections continue toward Interstate 91 and regional corridors.

Along its length, the highway crosses varied topography, from urban waterfronts adjacent to Boston Harbor to river valleys and mountain passes near Franconia Notch State Park and Pinkham Notch. The route interfaces with major transportation facilities including Logan International Airport, regional rail stations served by MBTA, and bus terminals linking to Port Authority-type operations. Interchanges provide access to major highways including Interstate 95 (Massachusetts Turnpike), Interstate 495, and Interstate 89 in Vermont. The corridor supports commercial freight movements to ports, distribution centers, and industrial parks such as those in Somerville, Massachusetts and Manchester, New Hampshire.

History

Planning for the route began in the 1950s as part of the original Federal-Aid Highway Act of 1956 system to improve connections among northeastern population centers. Early segments in the Boston area reused existing limited-access alignments and displaced older corridors, intersecting with projects like the Central Artery and the Massachusetts Turnpike expansions. Construction milestones included completion of urban sections in the 1960s amid controversy over impacts to neighborhoods like those affected by the Big Dig project in downtown Boston and adjacent historic districts. Suburban extensions through the Merrimack Valley and into New Hampshire were completed in phases, with the Salem, New Hampshire and Windham, New Hampshire interchanges opening in later decades to support commuter growth.

In northern New Hampshire, roadway improvements in the 1970s and 1980s enhanced access to the White Mountains tourism economy, linking to attractions such as Mount Washington Auto Road and resorts near North Conway, New Hampshire. Environmental reviews influenced alignments near protected areas like Franconia Notch State Park, where balancing mobility and conservation shaped design decisions. In Vermont, the terminus area was adjusted in coordination with Vermont Agency of Transportation plans and federal funding cycles. Major reconstruction projects, including corridor widening and interchange reconfiguration, have responded to increased traffic volumes, winter maintenance demands, and multi-modal planning efforts tied to agencies such as Massachusetts Department of Transportation and New Hampshire Department of Transportation.

Major intersections

The highway intersects numerous principal routes and corridors that facilitate regional connectivity: - Southern urban interchanges near Kendall Square connecting with local arterials and ramps to Massachusetts Route 3 and U.S. Route 1. - Junction with Interstate 95/Route 128 in the northeastern Boston suburbs providing circumferential access to Woburn, Massachusetts and Reading, Massachusetts. - Interchange with Interstate 495 near the outer Boston suburbs, linking to Marlborough, Massachusetts and Lawrence, Massachusetts. - Connections with U.S. Route 3 and Route 110 through the Merrimack Valley and Lowell, Massachusetts region. - Crossings with U.S. Route 4 and New Hampshire Route 16 as the highway approaches the White Mountains corridor and Conway, New Hampshire. - Junctions with Interstate 89 and access toward Montpelier, Vermont and Burlington, Vermont via regional routes near the northern terminus. These interchanges link to hubs such as Logan International Airport, Manchester–Boston Regional Airport, and rail connections at stations serving MBTA and regional carriers.

Auxiliary routes

Several auxiliary and related corridors serve the primary alignment, providing urban and regional relief: - Spur and connector routes that feed downtown Boston and Cambridge complexes, interfacing with Central Artery remnants and local expressways. - Bypass and business loops in New Hampshire communities such as Nashua, New Hampshire and Manchester, New Hampshire that channel traffic toward commercial centers and historic districts. - Short state-designated connectors in Vermont that transition traffic to U.S. Route 2 and Interstate 91 corridors, facilitating interstate freight and tourism movements toward St. Johnsbury, Vermont. These auxiliary facilities are coordinated with state agencies including Massachusetts Department of Transportation, New Hampshire Department of Transportation, and Vermont Agency of Transportation.

Future and improvements

Planned projects focus on congestion relief, safety upgrades, and multimodal integration. Urban reconstruction efforts continue to reconcile legacy infrastructure with modern standards near Boston, including interchange modernization influenced by lessons from the Big Dig and transit-oriented planning with MBTA expansions. In New Hampshire, capacity upgrades and winter-weather resiliency projects aim to improve access to tourist nodes such as North Conway, New Hampshire and Franconia Notch State Park. Vermont corridor initiatives emphasize pavement rehabilitation, bridge renewal, and improved connections to Interstate 91 for freight efficiency. Funding and environmental review processes involve federal initiatives under programs related to the Federal Highway Administration and state transportation plans coordinated with regional planning organizations.

Category:Interstate Highways in New England