United States Senate chamber

The United States Senate Chamber is a room in the north wing of the United States Capitol that serves as the legislative chamber of the United States Senate, since January 4, 1859. The Senate first convened in its current meeting place after utilizing Federal Hall, Congress Hall, and the Old Senate Chamber in the Capitol building for the same purpose.

The chamber, designed by then-Architect of the Capitol Thomas Ustick Walter, is a rectangular two-story room with 100 individual desks, one per Senator, on a multi-tiered semicircular platform facing a central rostrum in the front of the room. The Senate floor itself is overlooked on all four sides by a gallery on the second floor. The Senate floor itself is 80 by 113 feet (24 by 34 m).

The Senate convened, beginning in 1790, in a second-floor chamber in Congress Hall in Philadelphia, Pennsylvania until moving into the Old Supreme Court Chamber in the Capitol building in 1800. From 1810 to 1859, the Senate utilized the Old Senate Chamber for legislative functions.

During this time, the Senate nearly doubled in size as new states were admitted to the Union. In light of the increased size of both houses of congress, two new wings were added on to the United States Capitol. Beginning in 1851, the Capitol underwent several expansions including the new wings and their respective chambers, as well as a new dome.

In addition to expanding the space available for the Senate's use, the chamber's designers were concerned that the room have acoustical and line-of-sight qualities comparable to those of a theater. The construction of the chamber began in 1851 and continued until senators began utilizing the room for legislative business in 1859. Shortly after beginning to utilize the chamber, however, senators noted the poor acoustic qualities, the sounds created by rain as it hit the glass-paneled ceiling, and uncomfortable drafts of air throughout the room.

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