State Route 100 (SR 100) is a state highway in the U.S. state of Maine, running from Portland to Bangor. The south end of SR 100 is at the intersection of Forest Avenue and Cumberland Avenue in downtown Portland. Its north end is at the intersection of Hammond Street, Main Street, State Street and Central Street in downtown Bangor; SR 100 runs along Hammond Street with U.S. Route 2 (US 2) which continues across Main Street/Central Street onto State Street.