Shown here docked at the south end of Gangplank Marina.
From
http://www.odyssey.com/dc/about_ship/360_tour.cfm:
Voted Distinctive Passenger Vessel of 1995 by Marine Log and Outstanding Passenger Vessel of the Year by Maritime Reporter, Odyssey III is the only ship of its kind in the U.S. Its unique design allows for travel beneath the historic bridges spanning the Potomac. Newly-renovated, glass-atrium dining rooms offer spectacular panoramic views of the nation's greatest monuments. The open-air perimeter deck is perfect for watching the District drift slowly by. The exterior boasts a quarter mile open-air perimeter deck.