Boating: Whether you want to canoe, kayak or get competitive with some rowing, several boathouses in the area will set you up. Try Thompson Boat Center, where you can rent a canoe, kayak or sunfish sailboat--or even join a competitive rowing team. At Jack's Boathouse on the Georgetown Waterfront you can rent a canoe or kayak, and now they're renting those stand-up paddle boards made famous by so many celebs.
Sailing: If you want to feel the wind in your sails but don't know the difference between port and starboard, make an appointment at Washington Sailing Marina, where you can get a sailing lesson.
Fishing: The falls and rapids on the Potomac River just west of Georgetown are home to smallmouth bass, rainbow trout, perch and other freshwater fish. For fishing advice and to pick up a DC license, stop by Fletcher’s Boathouse. It’s nestled along the C&O Canal just west of Georgetown, and the staff always knows what’s biting.
Theodore Roosevelt Island: Dedicated to the 26th president of the United States, the island pays tribute to Teddy's conservationist spirit. Paddle up to the island or cross the walking bridge to explore. Pack a picnic and amble around the island to see the wildlife.