8:30 a.m.-6 p.m., Concord Museum, 53 Cambridge Turnpike. Ride for the Concord Museum to mark the 250th anniversary of the start of the American Revolution. Choose between a 21.3- or 32.4-mile loop. Post-ride party at the museum includes food, drink, and entertainment. $50 entry fee; more information at concordmuseum.org.
