Harkness Memorial State Park

Over 230 acres of lawns, gardens, dunes and coastal grassland on Long Island Sound, centered on Eolia, the 42-room 1906 mansion of Edward and Mary Harkness. Fifteen of the park's 60 structures are on the National Register. Two trails, fishing, picnicking and birding — swimming is not permitted. Open daily 8 a.m. to sunset; mansion tours weekends and holidays, Memorial Day-Labor Day, 10 a.m.-2 p.m., last tour 1:30 p.m.