Like passenger rail itself, the Beaux Arts building was in decline, with chunks of the ceiling falling off and mushrooms growing on the floor.
Today, the 100-year-old building is a thriving transportation hub, a shopping mall and one of Washington's most visited sites with more than 32 million people passing through a year. The station will celebrate its centennial Oct. 4-5 with a display of historic locomotives and rail cars rarely seen in one place.
"The history of this station tracks in some ways with the railroad industry," said Joe McHugh, vice president for government affairs at Amtrak. The railroad, which is headquartered at Union Station, is taking the lead in the anniversary celebrations.
Amtrak was formed out of the ruins of once-grand private passenger rail service, which declined in the mid-20th century with the rise of air travel and the automobile. Recently, rail travel has undergone a modest resurgence. Some 25.8 million passengers took Amtrak in the last fiscal year - the most since the government-owned corporation started business in 1971.
The Union Station centennial falls on the 20th anniversary of the station's 1988 rehabilitation, and Amtrak is using it as an opportunity to showcase one of the nation's most successful makeovers.
"The restoration of the building gave us back one of the great architectural landmarks of Washington," said Dwight Young, who works for the National Trust for Historic Preservation.
Daniel Burnham, the principal architect of the 1893 Chicago World's Fair, designed the station to serve as "a monumental gateway to Washington," Young said. His creation opened in 1907, though it wasn't completed until the following year.
In the early decades, nearly everyone, including presidents and visiting royalty, arrived in Washington by train, making Union Station the first thing they saw.
On Jan. 15, 1953, a runaway train crashed through the main concourse. The floor collapsed under the weight of the locomotive, but nobody was killed. Just four days later, the damage was hardly visible when a special train for President Eisenhower's inauguration rolled into the station, according to an official station history.
But as passenger trains fell out of favor, so did big train stations. New York's original Pennsylvania Station, a similarly grand, classically-inspired structure, was razed in 1964.
Union Station survived, thanks in part to an ill-fated project to remake the building into a national visitor's center for the country's bicentennial. The marble floor was torn up to carve out a theater for an elaborate slideshow presentation.
The visitor's center was a flop, and soon the station was shuttered because of structural problems. Passengers used a makeshift Amtrak terminal behind Union Station, with a covered walkway around the building to get to the street.
A public-private partnership spent $160 million to restore the building. It reopened in 1988 - once again a train station, but this time with high-end retail and restaurants.
Amtrak has been trying to foster similar efforts - albeit on a smaller scale - around the country through its Great American Stations program. A renovated station can help spur development of neglected downtowns, advocates of such projects say.
Before Union Station's renovation, the thriving Capitol Hill neighborhood where it is located was "depressed," said David Ball, president of Union Station Redevelopment Corp., the nonprofit that holds a long-term lease to the building from the U.S. Department of Transportation. "We were sort of the catalyst."
The centennial celebration is Saturday, 10 a.m.-4 p.m., and Sunday, noon-4 p.m. The free event will feature an exhibit of historic locomotives and passenger cars from the heyday of rail travel, as well as modern Amtrak equipment. Visitors will be able to walk through the cars and even buy souvenir stamps inside an old railway post office car. Archival photos of the station will also be on display.