When the Pennsylvania Railroad and the Baltimore and Ohio Railroad announced in 1901 that they had agreed to build a new union station together, the city had two reasons to celebrate.
The decision meant that both railroads would soon remove their trackwork and terminals from the National Mall.
Though changes there appeared only gradually, the consolidation of the depots allowed the creation of the Mall as it appears today.
Secondly, the plan to bring all the city's railroads under one roof promised that Washington would finally have a station both large enough to handle large crowds and impressive enough to befit the city's role as the federal capital.
The station was to be designed under the guidance of Daniel Burnham, a famed Chicago architect and member of the U.S. Senate Park Commission, who in September 1901 wrote to the Commission's chairman, Sen. James McMillan, of the proposed project: "The station and its surroundings should be treated in a monumental manner, as they will become the vestibule of the city of Washington, and as they will be in close proximity to the Capitol itself."

After two years of complicated and sometimes contentious negotiations, Congress passed S. 4825 (58th-1st session) entitled "An Act to provide a union railroad station in the District of Columbia" which was signed into law by 26th President Theodore Roosevelt on February 28, 1903.
The Act authorized the Washington Terminal Company (which was to be jointly owned by the B&O and the PRR-controlled Philadelphia, Baltimore and Washington Railroad) to construct a station "monumental in character" that would cost at least $4 million (equivalent to $96.6 million in 2018). (
The main station building's actual cost eventually exceeded $5.9 million [equivalent to $143 million in 2018].)
Including additional outlays for new terminal grades, approaches, bridges, viaducts, coach and freight yards, tunnels, shops, support buildings and other infrastructure, the total cost to the Terminal Company for all the improvements associated with Union Station exceeded $16 million (equivalent to $386 million in 2018).
This cost was financed by $12 million (equivalent to $290 million in 2018) in first mortgage bonds as well as advances by the owners which were repaid by stock and cash.

Each carrier also received $1.5 million (equivalent to $36.2 million in 2018) in government funding to compensate them for the costs of eliminating grade crossings in the city.
The only railroad station in the nation specifically authorized by the U.S. Congress, the building was primarily designed by William Pierce Anderson of the Chicago architectural firm of D.H. Burnham & Company.
When the Pennsylvania Railroad and the Baltimore and Ohio Railroad announced in 1901 that they had agreed to build a new union station together, the city had two reasons to celebrate. The decision meant that both railroads would soon remove their trackwork and terminals from the National Mall. Though changes there appeared only gradually, the consolidation of the depots allowed the creation of the Mall as it appears today. Secondly, the plan to bring all the city's railroads under one roof promised that Washington would finally have a station both large enough to handle large crowds and impressive enough to befit the city's role as the federal capital. The station was to be designed under the guidance of Daniel Burnham, a famed Chicago architect and member of the U.S. Senate Park Commission, who in September 1901 wrote to the Commission's chairman, Sen. James McMillan, of the proposed project: "The station and its surroundings should be treated in a monumental manner, as they will become the vestibule of the city of Washington, and as they will be in close proximity to the Capitol itself."
After two years of complicated and sometimes contentious negotiations, Congress passed S. 4825 (58th-1st session) entitled "An Act to provide a union railroad station in the District of Columbia" which was signed into law by 26th President Theodore Roosevelt on February 28, 1903. The Act authorized the Washington Terminal Company (which was to be jointly owned by the B&O and the PRR-controlled Philadelphia, Baltimore and Washington Railroad) to construct a station "monumental in character" that would cost at least $4 million (equivalent to $96.6 million in 2018). (The main station building's actual cost eventually exceeded $5.9 million [equivalent to $143 million in 2018].) Including additional outlays for new terminal grades, approaches, bridges, viaducts, coach and freight yards, tunnels, shops, support buildings and other infrastructure, the total cost to the Terminal Company for all the improvements associated with Union Station exceeded $16 million (equivalent to $386 million in 2018). This cost was financed by $12 million (equivalent to $290 million in 2018) in first mortgage bonds as well as advances by the owners which were repaid by stock and cash.
Each carrier also received $1.5 million (equivalent to $36.2 million in 2018) in government funding to compensate them for the costs of eliminating grade crossings in the city. The only railroad station in the nation specifically authorized by the U.S. Congress, the building was primarily designed by William Pierce Anderson of the Chicago architectural firm of D.H. Burnham & Company.
Washington Union Station