WASHINGTON — When it opened in 1956, the Statler Hilton Hotel in Dallas was a marvel of modern architecture, its size a tribute to imagination and a booming economy. Now it stands empty, another white elephant on the American landscape.

On Tuesday, the National Trust for Historic Preservation, a private nonprofit organization, will announce that the Statler Hilton and 10 other sites have made its 2008 list of the country's most endangered historic places.

"Historic buildings in cities all over the country, they are being changed and destroyed," said the trust's president, Richard Moe, noting that scores of other sites could have been added to the list.

The Statler was chosen because it represents an important moment in the history of Dallas, a time of growth and success, the trust said. Buildings of midcentury modern design are at risk of demolition around the country. The Statler, designed by William Tabler, was the first glass-and-steel hotel in America.

The City of Dallas is hoping that the designation will bring attention to the building's plight and attract a buyer for the building, which is owned by a corporation based in the British Virgin Islands, Hamsher International Limited. But any renovation could be complicated by environmental issues, and potential buyers might be put off by the city's razing of a parking structure across the street to install a park.

The city says that it is willing to help the buyer, and that the park gives greater prominence to the building. Thomas Keen, a lawyer for the corporation that owns the building, said the hotel was for sale but doubted that the designation would draw buyers.

The trust's list also includes the Lower East Side of New York, whose historic character is imperiled by development, and a neighborhood in Buffalo that dates to the 1850s, Peace Bridge, where as many as 100 homes and businesses face demolition so the Department of Homeland Security can increase the size of a plaza at the Canadian border.

Also on the list is the Sumner School in Topeka, Kan., the all-white school that excluded a black student, leading to the Brown v. Board of Education decision. The list also includes Charity Hospital in New Orleans and its adjacent neighborhood, along with Boyd Theatre, the last of the Art Deco movie palaces in Philadelphia.

The California state park system is making the list because decades of budget cuts have left it in grave danger, the trust said. Even though Gov. Arnold Schwarzenegger said last week that he would not follow through on a plan to cut 10 percent from the state parks budget, the system is still in danger, said Elizabeth Goldstein, the president of the California State Parks Foundation.

Completing the list are Great Falls Portage in Montana; Hangar 1 at Moffett Field in Santa Clara County, Calif.; the Michigan Avenue street wall in Chicago; and Vizcaya and Bonnet House in Florida.

The trust's annual designations, which began in 1988, do not confer any legal protection. And though the future of many of the places is uncertain, only seven of the more than 200 sites listed over the last 20 years have been lost.

"There is a cost to every loss," Moe, the trust president, said. "We don't argue that every old building should be saved, but the purpose is to illustrate the most important kinds of structure or sites that can and should be saved."