Chris Corsentino was four years old when he sailed from New York to Germany, for his dad’s army assignment, aboard the SS United States, in 1959.

"I remember being in the playroom with my brother. They had hobby horses with wheels and we would get on those little hobby horses on one end up against the wall and wait for the ship to hit a swell and then we'd roll down to the other side," Corsentino said.

The ship was about as long as three football fields laid end to end and had more than 400 passenger rooms. It was put into service in 1952 but sailed for less than two decades as people transitioned to plane travel to go abroad. It was taken out of service in 1969 and it sat for decades at various ports around the country. But last year Florida’s Okaloosa County purchased the ship and it’s now anchored in Mobile, Alabama.

Its next life is going to be underwater as the world’s largest artificial reef.

Before it’s sunk workers must strip anything non-metal off the ship and clean out contaminants like old fuel. Eventually the giant ocean liner will be towed and then sunk off the coast of Destin, Florida.

"By creating a reef with something as iconic as the SS United States it's going to bring a lot of people to the destination to go fishing and diving," said Okaloosa County’s Natural Resources Chief, Alex Fogg.

The Florida coast is full of artificial reefs, from cement pyramids to even some smaller ships. "So it'll be kind of that flagship, if you will, for our artificial reef program," Fogg said.

In other words, it’ll be a marketing bonanza. Fogg expects the SS United States alone will bring in about $5 million in annual economic impact to the region. In all, Florida’s artificial reefs foster an estimated $3.1 billion recreation and tourism industry.

For now, as preparations for the big sink continue, the ship is generating a little tourism boom in Mobile, too.

Willie Jones is the captain of a riverboat called the Perdido Queen. Usually he takes people out for dinner cruises on the Mobile River but his most popular tour now is to the SS United States. In the three years before the ship's arrival Jones had taken out three or four 20-person cruises to the port, where the SS United States is currently berthed. "Now that the ship is here, in March we took out 1,502 people to see it," he said. His little riverboat gets up close to the hulking ship.

"Most of these people are coming from out of town, so they're staying in the hotels, eating at the restaurants," Jones said. "It's been a big influx for everybody."

Some 50 people climbed aboard the Perdido Queen on a recent Friday afternoon. Jones blasted the horn as he departed. About 10 minutes later the ship came into view.

"All right, there she is," Jon Robitaille, the guide, said over a speaker system. "The SS United States — 990 feet in length, making her 100 feet longer than the Titanic."

Visitors came out to gaze at the imposing wall of black metal that rose before them. From the ship’s deck, workers looked like ants. They waved at the tourists.

Chris Corsentino, who sailed on the SS United States as a four-year-old, said this was his second time taking the tour.

"It's an old dame. It's beautiful," he said. "It's like an old friend. I feel like I should pull over and give it a kiss."

He was one of five people on the tour that afternoon who had spent time on the ship when it was in service and who came to say goodbye before the SS United States descends to the ocean floor.