Washington D.C. was the capital of the United States. It covered the same area as the District of Columbia, which is located between Virginia and Maryland.
After reveals that the Yellowstone Caldera erupted and the subsequent ash cloud would reach Washington in seven hours, Anheuser, Helmsley, and First Daughter Laura Wilson and several other government officials evaluate with the White House and board Air Force One, with Wilson staying to address the nation one last time.
Washington is seen being covered in a volcanic ash cloud that erupted from the Yellowstone Caldera in the night, with many refugees from earthquake-battered cities moving to the White House and President Wilson staying with his people. It was later hit by a massive 9.4 magnitude earthquake which centered in North Chesapeake Bay that caused everyone to struggle to stand and survive. Shortly, it destroyed the Washington Monument, killing everybody outside the White House.
While the Earth's crust was being shifted, President Wilson, who was of the remaining survivors of the massive earthquake, wakes up and sees the USS John F. Kennedy along with a mega-tsunami heading to the White House which results in his death after being crushed by the USS John F. Kennedy and the White House being destroyed and swept away along with most of the remaining buildings that stood.
In the aftermath of the apocalypse, the remains of Washington D.C are submerged underwater and is rendered uninhabitable from the apocalyptic disasters.