Built during 1941 as the Lexington County Airport, this airfield became the Columbia Army Air Base shortly after the U.S. entered World War II in December 1941. The base was used to train crews for medium bombardment groups flying B-25s and A-26s, reaching a military population of 7,800 in February 1945, and it reverted to standby status after the war. In February 1942, twenty-four B-25 bomber crews of the 17th Bombardment Group at Columbia Army Air Base volunteered to take part in a secret project headed by Lt. Col. James H. Doolittle. This group was the nucleus of the Doolittle Raiders who took off from the aircraft carrier Hornet and bombed Tokyo on April 18, 1942.