This 1713 stagecoach inn was providing sustenance to travelers between Boston and New York long before the Revolutionary War, but that conflict provided it with its object of greatest note. A British cannonball is embedded in one of its walls, presumably fired during the Battle of Ridgefield in 1777. The tavern is now a museum of Colonial life, with period furnishings and costumed guides, and listed in the National Register of Historic Places. And it has another claim to fame: Keeler was long the summer home of architect Cass Gilbert (1849-1934), who designed the Supreme Court Building in Washington, D.C., and was a key figure in the construction of the George Washington Bridge in New York. Visits are by guided tour.