If you're driving through the area, take a look at this 1756 stone fort. Its primary role in Civil War history was as a post for Union troops, though it faced Confederate raiders once in December 1861. During the French and Indian War, it served as an important supply base for English campaigns; during the Revolutionary War, it was a refuge for settlers and a prison for Hessian and British soldiers. Daily in summer and on weekends in spring and fall, living-history reenactors show visitors about frontier life. The park also has campsites for $15 a night (tel. 888/432-2267), two hiking trails through woods and wetlands, and boat rentals. Nearby is the 23-mile Western Maryland Rail Trail along an old train line. The Rails to Trails Conservancy named this one of the top 12 U.S. trails for viewing fall foliage.