One of the most famous landmarks in the United States is the United States Capitol with the dome adorning the roof line. The dome of the Capitol, with its pure white sandstone, is radiant, a symbol of democracy and strength. An impressive site when lit up at night it is a fitting end to the building it crowns. Located on Capitol Hill in Washington, DC, it houses the Senate and House chambers of the legislative branch. It is one of the most symbolic and architecturally impressive buildings in our Nation.

The design of the original dome began with a Capitol design competition organized by Thomas Jefferson, who was Secretary of State under President George Washington. The prize is $500.00 and a lot from the city to whoever has produced the winning plan. 17 plans were submitted, none of which were approved. Then, in the fall, a letter arrived from Dr. William Thornton, requesting the opportunity to present a plan, which the commissioners granted. The building was characterized by a central cupola (dome).

The dome would sit over the rotunda and was a two-dome structure. The inner dome rose 96 feet above the rotunda floor and was built of stone; the exterior was a wooden dome with a copper roof and rose 140 feet. The floor of the Rotunda was illuminated from the oculus at the top of the dome. Thomas Jefferson called it “the first temple dedicated to the sovereignty of the people.”

As the United States grew and more states joined the Union, the Capitol needed to be expanded. Extensions to the north and south were built. With these additions, the original dome was not aesthetically pleasing. To achieve balance, the size of the dome had to be in proportion to the length of the uninterrupted roof line. The old dome was a fire hazard as it was made from a wooden frame. For these reasons, a new fireproof dome was considered necessary. This was the most ambitious undertaking in the history of American architecture.

The wooden dome was removed in the fall of 1856. The new dome was three times the height of the original dome and constructed of cast iron with columns, pilasters, dozens of windows, and topped with a statue. A large painting of the Apotheosis of Washington was painted on a shell and the canopy is suspended between the inner and outer dome and is visible through the oculus at the top of the inner dome. Apotheosis is a Greek word meaning ‘to raise to the stature of a god’.

Domes with their circular shape have been called the perfect architectural form, the circle being a symbol of the universe. In religious architecture, domes proclaim the glory of God. The oculus or eye of the dome is considered the gateway to the Sun. From this portal at the Summit of the Dome rises the World Axis, the link between heaven and earth.

The Rotunda is a circular room located on the second floor of the Capitol over which the dome would be placed. It is this room that has served as the ceremonial center of the United States Capitol and known as the symbolic and physical heart of the United States Capitol.

As the United States grew, it is clear that state governments viewed the dome of the United States Capitol building as the American architectural icon of choice. Many states chose to emulate the structure to varying degrees in the construction of their own state capitols by incorporating a central cupola or cupola into their designs.

The dome has gained a commanding presence on America’s skyline, a symbol of democracy and the aspiration to allow all citizens to live a free and dignified life.