Diamond Head Lighthouse in Honolulu on Oʻahu has served as an active United States Coast Guard station since it was first lit on July 1, 1899. Originally a forty-foot iron tower within coral rock walls, it was rebuilt in 1917 as a fifty-five-foot reinforced concrete tower on the original foundation, with a nearby residence added in 1921 and automation following in 1924. The Coast Guard took over in 1939 and operated a radio station there during World War II; veteran Melvin Bell later recalled serving at the site during the attack on Pearl Harbor. The lighthouse has since remained both a working facility and a recognized historic landmark.