Cannon House Office Building

The Cannon House Office Building, completed in 1908, is the oldest office building of the United States Congress in Washington, D.C. and a significant example of the Beaux-Arts style of architecture. Originally designed by the firm of Carrère and Hastings, it was constructed to provide office space for members of the House of Representatives and featured state-of-the-art facilities for its time, including forced-air ventilation systems and steam heat. The building has undergone several renovations, including a major expansion in 1913 and a renovation project that began in 2015, which will cost $752.7 million and take 10 years to complete.learn more on wikipedia