Don't know if this qualifies because it closed and later re-opened, but The Willard Room opened in 1850 with a famous murder in the room on May 8, 1856 by Congressman Philemon T. Herbert shooting his Irish waitor Thomas Keating. Keating had refused to serve Herbert breakfast after the designated breakfast hours. The pair had an argument that errupted into a physical fight, then into gunfire. Also, Abraham Lincoln was smuggled into the Willard Room in 1861 just before his Jan 21 inauguration. Lincoln was escorted by Alan Pinkerton of the famous Pinkerton Agency, an agency that created today's Secret Service. But, the Willard Hotel closed its doors in 1968 and did not re-open until 18 years later in 1986 (Sept 23). While the Willard Room dining room was out of commission for 18 years it still maintained its original luster, original name and past guests returned. So while it was not in continuous operation, it is still DC's oldest restaurant to date.
