Philadelphia: City Hall
Philadelphia City Hall, located on Penn Square, is the seat of all three branches of government for the city of Philadelphia. Construction started on the Second Empire-style design by Scottish-born architect John McArthur, Jr. in 1871 and although topped off in 1894, the interior wasn't completed until 1901. Designed to be the world's tallest building, it was surpassed by both the Washington Monument and Eiffel Tower during construction, but was still the world's tallest habitable building, at 548-feet, at the time of its completion until 1908. It held the distinction of tallest building in Philadelphia, owing to a development gentleman's agreement, until 1987.
City Hall is the tallest and largest masonry building in the world. Without a steel frame, its weight is borne entirely by granite and brick walls as thick a 22-feet. The central tower reaches a height off 511-feet and is topped by a 37-foot, 27-ton bronze statue of William Penn, one of 250 sculptures created by Alexander Miline Calder adorning the building. Each of the tower's four sides is faced with a a clock, 26-feet in diameter and designed by Warren Johnson. The buildings more than 600 rooms are organized around a central courtyard reached through large archways on each of the four sides.
In 2007, Philadelphia City Hall was ranked #21 on the AIA 150 America's Favorite Architecture list.
NRHP Reference #76001666 (1976)