Although not well known outside Virginia, George Mason (1725-92) was one of the most liberal and creative political thinkers of his time. He wrote the Virginia Declaration of Rights, upon which Thomas Jefferson drew for the Declaration of Independence in 1776. Mason also helped draft the Constitution but refused to sign it because it didn't abolish slavery or initially contain a Bill of Rights. Built between 1755 and 1759, his one-and-a-half story brick house is a fine example of Colonial Georgian architecture. The restored formal gardens focus on the 12-foot-high English boxwood-lined walkway believed to have been planted by Mason. (That's right: The shrubs could be more than 250 years old!) George and Ann Mason are buried here in the family graveyard. An 11-minute film will introduce you to Mason and his estate. You must then take a 30-minute tour in order to enter the mansion. En route to the house, you'll pass a small museum of Mason family memorabilia. A nature trail goes down to the Potomac (you cannot see the river from the mansion).