The Charles H. McClenahan Memorial Reef is named after Charles “Mac” McClenahan, a former Department of Defense employee with 50 years of service. Beginning in 1964, Mac spent 20 years of his 22-year stint at the Eglin Air Force Base (AFB) as part of the Explosive Ordinance Disposal team. He then went on to spend 28 years in the Civil Service, with a specialty in weapons and munitions. His main focus of work was concrete structures and how best to defeat them. His work led to the destruction of an untold number of concrete targets over the years. The memorial reef, known colloquially as “Mac’s Reef,” is fittingly made up of old concrete targets from nearby Eglin AFB. The southern half of the site consists of concrete culverts also provided by the base. The site is popular with divers due to its complex habitat, shallow depth and its relative proximity to the pass. In September 2020, a 9/11 memorial was added to the site’s northeast corner featuring steel and concrete pieces from the World Trade Center and the Pentagon.