Route 126 is a 33.5704-mile-long (54.0263 km) north–south state highway in Massachusetts. Its southern terminus is a continuation of Rhode Island Route 126 by Woonsocket, Rhode Island and its northern terminus is at Route 2 and Route 2A in Concord. Along the way it intersects several major routes including Interstate 495 (I-495) in Bellingham, Route 9 in Framingham, and U.S. Route 20 in Wayland.

Route 2 is a 142.29-mile-long (228.99 km) major east–west state highway in Massachusetts, United States. Along with Route 9 and U.S. Route 20 to the south, these highways are the main alternatives to the Massachusetts Turnpike/I-90 toll highway. Route 2 runs the entire length of the northern tier of Massachusetts, beginning at the New York border, where it connects with New York State Route 2, and ending near Boston Common in Boston. Older alignments of Route 2 are known as Route 2A.