Why this six-sided building is named the Octagon remains a subject of debate. Some say that even though the main room is a circle, it resembled octagonal rooms common in England (these rooms were actually circular as well, but called octagon salons because they were constructed of eight walls and then plastered heavily in the corners to make a circle). Others say it's for the eight angles formed by the odd shape of the six walls—an old definition of an octagon. Either way, the building is considered one of the best examples of Federal architecture in the United States, and offers visitors an opportunity to learn about life in the city at the birth of the new nation's capital. Designed by Dr. William Thornton (original architect of the U.S. Capitol), the Octagon was built for John Tayloe III, a wealthy Virginia plantation owner, and was completed in 1801. Thornton chose the unusual shape to conform to the acute angle formed by L'Enfant's intersection of New York Avenue and 18th Street.
Interior details show how architecture was used to display wealth and also accommodate both the homeowners and their servants.
After the British burned the White House in 1814, Thornton convinced the Tayloes to allow James and Dolley Madison to stay in the Octagon. From September 1814 until March 1815, the Octagon became the temporary White House. It was in the second-floor study that the Treaty of Ghent, which ended the War of 1812, was ratified. By the late 1800s, the house had fallen into disrepair and remained so until the American Institute of Architects (AIA) purchased it in 1902. AIA used the house for its national headquarters before the construction of the rather unexceptional building behind it.
Renovations have revealed such details as the intricate plaster molding and the original Coade stone fireplace surrounds (named for the family that crafted a now-lost method of casting crushed stone) and returned the Octagon to its 1815 appearance, topped off by a historically accurate, cedar-shingle roof with balustrade. Historically-furnished rooms include the parlor, dining room, treaty room and basement kitchen. Second floor gallery spaces hold temporary exhibits on architecture and design. Guided tours for groups of any size are available outside of these hours by appointment for $10/person (call 202/626–7439 or email email@example.com).