The Opana Radar Site is a National Historic Landmark that commemorates the first operational use of radar by the United States in wartime, during the attack on Pearl Harbor. It is located off the Kamehameha Highway just inland from the north shore of Oahu, Hawaii, south of Kawela Bay. It is not open to the public.
Today, a modern Navy telecommunications station occupies the top of the Opana Hill adjacent to the site. Since the 1941 radar was a mobile, there is no physical evidence of the historic unit at the site.