The SS United States, once the fastest ship in the world, sits dockside in Philadelphia, Pennsylvania. Norwegian Cruise Lines is studying the ship's future.

PHILADELPHIA - 
I saw a ghost on the way to a baseball game.

Running late to see the Phillies play at Citizens Bank Park in Philadelphia, I asked the desk clerk at the Sheraton Society Hill for an alternative to bucking rush-hour traffic on Interstate 95. Sure, he said, take the road along the waterfront.

It was a great tip, and I was soon speeding past the new big boxy stores that are rapidly replacing the shuttered warehouses along the banks of the Delaware River. I passed the USS Olympia, the Spanish-American War battleship that served as Admiral Dewey’s flagship in the Battle of Manila Bay. It’s a museum. Across the Delaware River, I could see the battleship USS New Jersey at anchor. It served from World War II to the run-up to the Persian Gulf War and is a museum now, too.

Nearing the ballpark, I saw another legendary ship, the white letters ‘‘UNITED STATES’’ still recognizable on the raked prow that could cut through the heaviest seas. Thick chains tied down a maritime thoroughbred grown rusted and dirty, left to rot at a pier. The sealant meant to ward off the elements gave the ship a muted, blurry look.

Like a ghost.

A lonely billboard attached to the chain link, erected by the SS United States Conservancy, showed the ship in its prime.

The SS United States was once the fastest big ship in the world. It was the last true ocean liner to win the coveted Blue Riband awarded to the ship that makes the fastest crossing of the North Atlantic. When it steamed from Southampton to New York in three days, 12 hours and 12 minutes in July 1952, the ship knocked nearly nine hours off the previous record, set by the Queen Mary in 1938.

Officially, the top speed of the SS United States was 35 knots. But the Pentagon had secretly helped design the ship, which would have been used as a troop transport in case of a Soviet invasion of Western Europe. The top speed was actually closer to a remarkable 44 knots, about 50 mph. The Queen Mary had a top speed of just over 30 knots.

But the SS United States’ heyday was brief - less than a decade. By 1958, jets were revolutionizing trans-Atlantic travel. The SS United States saw its clientele slowly slip away. Removed from service in 1969, it was sold and moved repeatedly until arriving in Philadelphia in 1996. Some civic boosters ridiculed the once storied ship as an eyesore.

Three years ago, it appeared there might be a happy ending to the saga of the SS United States. The ship has devoted and active fan clubs. The SS United States Foundation, lobbied for the ship to be turned into a floating museum and hotel - something along the lines of an East Coast version of Long Beach’s Queen Mary.

But even the most starry-eyed romantic never dreamed the ship might sail once again.

Then Norwegian Cruise Lines struck a deal in April 2003 to return the SS United States to service, most likely as a cruise ship in Hawaii. Because the United States was American-built, it was one of the few ships that could meet a law requiring ships carrying passengers between U.S. ports either be American built or registered. Norwegian previously had to make a two-day detour to Fanning Island to get around the law.

The resurrection of the old steamship wasn’t a pipe dream. Nearly all modern cruise ships run on diesel fuel. But Norwegian had prior experience restoring a venerable steamer.

The company had saved the SS France in 1974, renamed the steamship SS Norway, then sunk an additional $120 million into refurbishing the ocean liner to operate as a Caribbean cruise ship.

Things got so giddy that SS United States fans stopped worrying about the wrecker’s torch and shifted their debate to how to keep Norwegian from altering the ocean liner’s classic low silhouette by adding decks, as it had with the SS Norway.

A month later it all blew up - literally. The Norway’s aging boilers exploded off Miami, killing four crew members. The ship was later transferred to Star Cruise Lines, renamed the SS Blue Lady. It now sits idle in Malaysia amid questions about the safety of steamships. Norwegian Cruise Lines opted to register other ships as American to operate the Hawaiian service.

Officially, the SS United States project is still afloat. Susan Robison, a spokeswoman for Norwegian Cruise Lines, said engineering studies show the ship is essentially seaworthy but would have to be brought up to more stringent safety codes and modern levels of luxury.

‘‘The evaluation of the ship, as built, to these standards is a critical step before we can move forward,’’ Robison said. ‘‘This feasibility study continues.’’

But many doubt the SS United States will ever see the seas again. The rebirth of steamship travel could be stillborn.

‘‘I have a great deal of doubt about Norwegian Cruise Lines’ commitment to putting the Big U back to sea,’’ said Robert Westover, chairman of the SS United States Foundation. ‘‘How long does a feasibility study take? More than 2 1/2 years? We’re not talking about rebuilding a nation here. My personal feelings are that they are stalling.’’

John Maxtone-Graham, who has authored many books on ocean liners and regularly lectures on Cunard’s trans-Atlantic voyages, has fond memories of the SS United States. But he believes all the good wishes and nostalgia will likely come to naught.