Massachusetts Route 10

Massachusetts Route 10 is a 60.69 mi north–south state highway that runs from the Connecticut state line at Southwick to the New Hampshire state line at Northfield. Originally part of New England Route 10 from 1922 to 1927, it continues to the south as Connecticut Route 10, and to the north as New Hampshire Route 10.

Route description
Route 10 crosses the border from Granby, Connecticut into Southwick, Massachusetts, overlapped with U.S. 202. It runs north through the Pioneer Valley towns of Southwick, Westfield, Southampton, Easthampton, Northampton, Hatfield, Whately, Deerfield, Greenfield, Bernardston, Gill, and Northfield. Route 10 has a long concurrency with U.S. 5 for about 25 mi from Northampton to Bernardston, where it was sometimes called the "5 & 10 Highway". During this concurrency, it closely parallels Interstate 91, with five exits from Northampton to Deerfield, with close access at Route 2 in Greenfield and another exit, solely for Route 10, in Bernardston. It crosses the Connecticut River in Northfield before entering New Hampshire.

Route 10 is concurrent with seven other routes (US 5, US 20, US 202, and Massachusetts Routes 57, 9, 116, and 63) for 43 mi of its nearly 61 mi in the state with three points of triple concurrency, leaving less than a third of its length as the sole road designation.

History
An odd sight greeted motorists in Easthampton in July 2005: standard issue Alabama state highway signs with the number 10 in a map of that state, instead of the standard Massachusetts square. This odd "Alabama 10" signage came about when a contractor mistakenly applied the sample from a federal manual. The signs have since been replaced with the correct shields.