Route 91 is a numbered state highway running 12.0 miles (19.3 km) in Rhode Island.

The route turns southeast, away from the Northeast Corridor and crosses through flat lands east of Westerly.

The road crosses through some small communities in Westerly, returning to a parallel with the Northeast Corridor.

[2] Route 91 leaves Alton and proceeds eastward into Wood River Junction, where it intersects with New Kings Factory Road, paralleling the Northeast Corridor.

Route 91 crosses the center of Wood River Junction at Switch Road, passing nearby Meadow Brook Pond.