Blackstrap Hill Community Forest
Blackstrap Hill is very popular with area mountain bikers. Its 520 acres hold over 9 miles of trails. There's a good mix of trails, from flowing singletrack through technical trails and even some borderline freeride stuff.
The trails here are pretty well marked and the blue and red trails get a lot of use.
This Strava map suggests which trails are the most popular and also suggest how the Community Forest's trails link into other nearby popular riding areas.
Printed maps are available at the Falmouth Town Hall and Public Works Building.