Historic Voyage: SS United States Becomes World's Largest Artificial Reef

The SS United States, the world's fastest ocean liner dubbed "America's Flagship," is taking its final voyage, destined to become the world's largest artificial reef off Florida's Gulf Coast.

The long-retired, 990-foot liner was purchased by Okaloosa County in Florida's Panhandle in October.

On Feb. 20, the ship left Pennsylvania, where it had been docked for nearly 30 years, guided by four tugboats.

After a stop in Mobile, Alabama for cleaning and renovation, the vessel will be sunk off Destin-Fort Walton Beach in Florida.

➤ Graphics: How SS United States, bigger than Titanic, will become world's largest artificial reef

Sighted off Palm Beach County's coast Wednesday, the ship was located off the Florida Keys Thursday.

Here's how you can track the liner's journey as it heads into the Gulf and to its destination:

In service from 1952 to 1969, the USS United States saw its share of famous passengers, including:

Marlon Brando
Coco Chanel
Sean Connery
Gary Cooper
Walter Cronkite
Salvador Dali
Walt Disney
Duke Ellington
Judy Garland
Cary Grant
Charlton Heston
Bob Hope
Marilyn Monroe
Prince Rainier and Grace Kelly
Elizabeth Taylor
John Wayne
The Duke and Duchess of Windsor

After a remediation process in Mobile expected to take about a year, SS United States will be towed south of Destin-Fort Walton Beach to be sunk. A date and location have not been revealed.

"Before her deployment in the Gulf waters, all of the environmentally unsafe materials will be removed. This includes all non-metal items, wiring and fuel. She will have holes strategically cut around the ship to ensure she lands upright as she is submerged. Passages will also be opened allowing for marine life to thrive in and around the ship. All of the preparations in Mobile are in close collaboration with multiple environmental agencies including the Department of Environmental Protection and Environmental Protection Agency," Destin-Fort Walton Beach's website states.

USS United States left Philadelphia Feb. 14, traveled down the Delaware River to Delaware Bay and out to the Atlantic. The estimated two-week journey takes the liner down the East Coast and into the Gulf on the way to Mobile, Alabama where it will be readied for its final move south of Destin-Fort Walton Beach to be sunk.

You can track the SS United States live. An interactive map provided by Okaloosa County, showing the liner's current location, can be found here.

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