United States Capitol - dome and visitor center

The United States Capitol's current cast-iron dome was constructed between 1855 and 1866, replacing an earlier wooden dome; the bronze Statue of Freedom was placed atop the dome in 1863. The Capitol serves as the meeting place of the U.S. Congress and contains the Rotunda, Statuary Hall, and the House and Senate chambers. The Capitol Visitor Center, a 580,000-square-foot underground addition, opened in 2008 to provide secure public access, exhibits, and orientation services for visitors.