The historic SS United States sank Wednesday in the Gulf of Mexico to become the world’s largest artificial reef after decades of sitting idle in Philadelphia.
Crews began flooding the 990-foot ocean liner with seawater shortly before 2 p.m. CST on Wednesday, Nov. 11, 2026, roughly 22 nautical miles southwest of Destin-Fort Walton Beach, Florida, according to AutoNotion.
The vessel settled into a targeted depth of 180 feet of water, joining more than 500 artificial reefs in Okaloosa County, PBS reported.
How the Record-Breaking Liner Met Its End
Built in Virginia between 1950 and 1951, the ship crossed the Atlantic from New York to Europe on its maiden voyage in July 1952 in just under three days and 11 hours, averaging 42 mph and capturing a trans-Atlantic speed record it still holds, CNN said.
Constructed largely of aluminum to save weight, the vessel measured nearly 1,000 feet long and stood 108 feet longer than the Titanic, having been built by more than 3,000 workers.
In its heyday, the luxury ocean liner hosted an array of prominent guests, including presidents and Hollywood stars.
Rising operational costs and the growth of commercial aviation forced the ship out of service in 1969, according to USA Today.
The vessel sat at Philadelphia’s Pier 82 for nearly 30 years before Okaloosa County bought the vessel for $10 million in October 2024 to repurpose it as a dive site and marine habitat, The Maritime Executive reported.
Why Explosives Were Barred From the Sinking
Federal environmental and explosives regulations prohibited the county from using controlled detonations to scuttle the vessel, CBS News reported.
Workers instead removed interior tanks, cut large holes into the decks, and removed more than 400 portholes to let water flood the hull, CBS News reported.
Before the deployment, the vessel underwent extensive remediation overseen by federal agencies including the U.S. Environmental Protection Agency, the Maritime Administration, the U.S. Army Corps of Engineers, and the Gulf and Atlantic States Marine Fisheries Commission.
More than four dozen people worked on the ship, according to Capt. Tim Mullane, who started Coleen Marine with his wife Coleen O’Malley in 2014.
“the fuel, the remaining fuel oil or contaminated water in the fuel tanks, liquids from the bilges, grease and doors from the water tight doors, or the elevators, and miles of wiring,” Alex Fogg, Okaloosa County’s chief of natural resources, said to USA Today of the extensive remediation work completed in Mobile, Alabama, alongside maritime company Coleen Marine.
“With a large reef like the SS United States, she’s so big that the wind is actually a factor — that wind could potentially move her off the site where we need to deploy her,” Nick Tomecek, public information officer for Okaloosa County, said to FOX Weather.
Marine Research Plans at the Wreck Site
Scientists from the Woods Hole Oceanographic Institution intend to monitor the site to study how marine organisms colonize a massive man-made structure from the outset, according to Newswise.
Researchers said that bacteria, algae, and fish would begin congregating around the newly formed reef within hours or days of the sinking.
“Understanding the controls on colonization of shipwrecks will also inform strategies for improving the effectiveness of artificial reef structures, including the design and engineering of materials that produce better artificial reefs and increase biodiversity,” said Kirstin Meyer-Kaiser, a marine biologist at WHOI, in a statement reported by Newswise.
HISTORIC DAY IN FLORIDA: FOX Weather Correspondent Brandy Campbell is witnessing history in Destin, Florida, as the SS United States is preparing to be intentionally sunk off the Gulf Coast and become the world's largest artificial reef. Brandy has a behind the scenes look and… pic.twitter.com/fioU7d7CLF
The upper decks of the sunken liner rest 60 feet below the surface, placing the highest sections within recreational diving limits on the Florida Panhandle Shipwreck Trail, The Independent reported.
The shipwreck reef will join the USS Oriskany, an aircraft carrier sunk as a dive site in 2006.
Earlier coverage: SS United States to Become World's Largest Artificial Reef in 2026
Related reading