Originally part of George Washington's River Farm, the Collingwood Library is now a unique library on Americana. With its extensive collection of books on American heritage and a genealogy section on loan from the Mayflower Society of Washington, the library features replicas of the Constitution and the Magna Carta. The nine-acre grounds, situated between Alexandria and Mount Vernon, offer picturesque views of the Potomac River at a place where ferries crossed the river in Revolutionary times. Open Monday and Wednesday through Saturday 10 a.m.-4 p.m., 1 p.m.-4 p.m. Sunday, Closed Tuesday.