White House
The White House, located in Washington, D.C., was the residence of the President of the United States and a seat of the American government.
In 1969, the Eleventh Doctor landed his TARDIS in the Oval Office of the White House, where he met President Richard Nixon. (DW: The Impossible Astronaut)
On Christmas Day 2009, President Barack Obama was giving a speech from the White House when, like everyone else on the planet, he was converted into a copy of the Master. (DW: The End of Time)
During the Orion War of the late 26th century, the President of Earth was based in the White House. (BFC: Scorpius, Fear, Conversion) In the year 4014 the President of Earth continued to be based in the Oval Office. (DWAM: Return of the Klytode)