20 photos that show how the Capitol building has changed over the years

Thornton's design featured a central building with two rectangular sections on its north and south ends for the Senate and the House of Representatives.

President George Washington selected his proposal in July 1793 and laid the cornerstone in September that year, according to the Architect of the Capitol. Congress met for the first time in the Capitol in 1800.

Congress temporarily met in the Blodgett's Hotel before finding a more long-term substitute at the Old Brick Capitol from 1815 to 1819. The site of the Old Brick Capitol is now the location of the Supreme Court.

Latrobe, who had worked on the design of the Capitol before the fire, made the Senate chamber larger and added marble from the upper Potomac River. Bulfinch redesigned the building's central section and worked on turning the wilderness surrounding it into a well-manicured lawn.

President Millard Fillmore chose architect Thomas U. Walter to lead the project.

The new dome was created with 8,909,200 pounds of iron.

The Statue of Freedom, which features a woman in a robe and headdress holding a sword in one hand and a laurel wreath of victory in the other, was designed by Thomas Crawford. His design was then cast in bronze by Clark Mills and completed with the help of a slave named Philip Reid. The 19.5-foot statue weighs about 15,000 pounds.

The terraces were designed by architect Frederick Law Olmsted.

The windowless room, which was built in 1857, was lit through a stained-glass skylight decorated with state seals.

The stained-glass ceiling was replaced with one of stainless steel and plaster, and the state seals were moved to the periphery, according to the Architect of the Capitol. Marble sculptures of 23 "Lawgivers" — thought leaders such as Hammurabi and Napoleon whose philosophies influenced the US legal system — were also added.

C-SPAN began broadcasting in the House in 1979.

Walter built the room without any walls to keep senators removed from distractions, but it did also have a skylight like the House.

The skylight was removed and replaced with a plaster ceiling, and the design of the ornamental wall pilasters was changed. The wooden speaking platform was also replaced with a marble one.

C-SPAN began broadcasting the Senate's activities in 1986.

The court met in what is now known as the Old Supreme Court Chamber from 1810 until 1860. The court then moved upstairs, and their chamber became the Law Library.

In 1901, the old Library of Congress space was turned into meeting rooms for congressional committees.

Famous events that took place in the room include President John Adams' address to the first joint session of Congress in 1800 and Thomas Jefferson's swearing-in ceremony in 1801.

The subway system was designed to help transport lawmakers between their offices and the House and Senate. The first version consisted of electric cars made by Studebaker, according to the Capitol's website. They were replaced by an electric monorail in 1912 and dual tracks in 1960.

Two lines run along the Senate side to the north, and one runs along the House side to the south.

The two-year restoration project fixed 1,000 cracks in the dome and gave it a fresh coat of paint, according to the Architect of the Capitol.

From its base to the top of the Statue of Freedom, the Capitol Building measures in at 288 feet tall.

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