The Diamond Head Lighthouse is built on the steep coast cliff of the extinct Diamond Head Volcano. The original lighthouse was built in 1899 and the original fresnel lens is still in use today. The current structure was erected in 1917. Built of reinforced concrete, the 55-foot lighthouse stands 147 feet above sea level and projects its light 18 miles out into the Pacific Ocean. The lighthouse is completely automated with a back-up battery in case of a power outage. The light keeper quarters were renovated and now serve as the residence of the 14th Coast Guard District Commander.
The fresnel lens atop the lighthouse has the intensity of 60,000 candlepower. The light shows a red sector to warn vessels away from the reefs of Waikiki Beach.