It runs from U.S. Route 1 (US 1) in Machias to an unnumbered road intersection in Machiasport.

The road heads west for about 100 feet (30 m) around a small memorial park before turning north onto O'Brien Avenue.

It heads past a few houses before marking a sharp turn to the east onto Elm Street.

Rim Road soon intersects the state route which provides access to Machaisport Station, across the Machais River.

The road curves to the west to enter the town center of Machaisport.