Route 121 (Rhode Island–Massachusetts)

Route 121 is a numbered state highway running 1.0 mi in Rhode Island and 4.4 mi in Massachusetts. It is part of the route connecting the city of Woonsocket (via Route 114) with the town of Wrentham.

Route description
In Rhode Island, Route 121 exists entirely in a rural section of Cumberland. It proceeds for 1 mi from an intersection with Route 114 along Wrentham Road to the Massachusetts State line. Now in Wrentham, Massachusetts, the road proceeds for 4.4 mi to an intersection with Route 1A. In Massachusetts, it is known as Cumberland Road and West Street.

History
The route from Woonsocket to Wrentham was assigned as Route 142 in the early 1920s when the New England states began numbering their state highways. Route 142 ran for about 11 mi between Route 122 and current Route 1A (then designated as U.S. Route 1). It used present-day Route 114 from Route 122 in Woonsocket and Cumberland, then along present-day Route 121 to Wrentham. Around 1933, the entire route (in both Rhode Island and Massachusetts) was renumbered as Route 11 and its northern end extended into Dedham along old Route 1 (current Route 1A) when Route 1 was realigned. Route 11 was later cut back to its original length after a few years when Route 1A was designated in the area.

In the mid-1960s, the southern end of the route was truncated by about 5.4 mi to its current southern terminus at the intersection of Pine Swamp Road and Diamond Hill Road in Cumberland. This was due to the westward extension of the Route 114 designation into the city of Woonsocket. At the same time, the route was renumbered to Route 121.