Introduction
United States Route 3 is an easily identifiable north-south United States Numbered Highway in Massachusetts and New Hampshire as well as the most significant border crossing into Canada from the U.S. State of New Hampshire, since no Interstate Highways connect the State of New Hampshire with the Canadian border directly. From north to south, Route 3 is identifiable for the Connecticut Lakes, for which the Third Connecticut Lake is extremely close to the international border; the Town of Pittsburg, New Hampshire, which includes the aforementioned lakes and is the largest Town in New England in terms of land area; the area of Franconia Notch; Laconia and Lake Winnipesaukee; Concord; Manchester; Nashua; and the Greater Boston area.
New Hampshire
Along United States Route 3, the aforementioned Town of Pittsburg serves as the northernmost torn in the State of New Hampshire, the largest New England town by land area, and home to the Connecticut Lakes and associated hiking trails, the Third Connecticut Lake trail for which parking is provided in the vicinity of United States Customs and Border Protection as the hiking trail cuts through Canada but is considered entirely within the United States with regards to identification as the trail does not provide access to the remainder of Québec and both begins and ends within the United States of America.
To the south of the Town of Pittsburg in Coös County are the communities of Clarksville, Stewartstown, Colebrook, Columbia, Stratford, Northumberland, Lancaster, Whitefield, and Carroll. After crossing out of Coös County, the first town encountered is the Grafton County town of Franconia, in which United States Route 3 must join Interstate 93 while the routes attempt to cut through Franconia Notch in a super-two configuration before the routes can diverge again. Even after the routes diverge, Route 3 will continue to follow along with and parallel Interstate 93, including into the communities of Lincoln, Woodstock, Thornton, Campton, Plymouth, Ashland, and Holderness within Grafton County.
Though United States Route 3 typically serves the role of paralleling Interstate 93 throughout the entirety of the route south of Franconia, the former actually diverges throughout the course of the Lakes Region, for which between the communities of Ashland to the north and Concord to the south, New Hampshire State Route 132 becomes the parallel route to the Interstate Highway. Within the area of the Lakes Region, however, United States Route 3 is often known for taking a more easterly route, including the Grafton County community of Holderness as well as the Belknap County communities of Meredith, Laconia (for which Route 3 is bypassed to the south and east though the United States Numbered Highway System contains a business route associated with the area), Belmont, Sanbornton, and Tilton. Though Northfield in Merrimack County is located nearby, the community, which Interstate 93 continues the north-south journey within, is only barely bypassed by United States Route 3.
Now in Merrimack County, United States Route 3 covers the communities of Franklin, Boscawen, Concord, Pembroke, Allenstowm, and Hooksett. To the south of Hooksett is Hillsborough County, notable for having two county seats: Manchester in the north and Nashua to the south. Both cities are located along Route 3, with the intermediate communities of Bedford and Merrimack also located along the highway. South of Nashua is the Commonwealth of Massachusetts, and more specifically Middlesex County, still within proximity of Interstate 93. Though Route 3 technically extends further south (beyond the Boston area) as a state route, the United States Numbered Highway only covers the areas further north. Such communities include Tyngsborough, Westford, Chelmsford, Lowell, Billerica, Bedford, Burlington, Woburn, Winchester, Arlington, and Cambridge—all in Middlesex County.