The Capitol

Sitting atop a high hill overlooking the National Mall and the wide avenues of the city beyond, the Capitol (built in 1793) is among the most architecturally impressive and symbolically important buildings in the world. It houses the legislative branch of Congress, the Senate and the House of Representatives. A 285 ft cast iron dome is topped by a bronze statue called the Statue of Freedom.
Several areas of the building are open to the public including Statuary Hall, the original Supreme Court chamber, and the crypt.
Admission is free and guided tours are done according to first-comefirst-served basis . 
Capitol Hill
Tel: (202) 225 6827
Website: www.aoc.gov
 

More Places-To-Visit in Washington-DC
Adams Morgan
Arlington Cemetery
Arlington House
Georgetown University
International Spy Museum
Jefferson Memorial