The expedition to a "lost city" in the Peruvian Andes that University of Colorado archeologists recently announced with great fanfare involved well-known ruins that are even touted in tourist guidebooks as an interesting place to visit.

At a Jan. 31 news conference, the Colorado archeologists described the site as a "lost city" and issued a news release headlined "Pre-Incan Find May Rival Machu Picchu," the famed mountaintop ruins of an Incan city in southern Peru.

"The site," Thomas Lennon, a leader of the expedition, said then, "has been the subject of rumors and unsuccessful expeditions since the beginning of this century, if not from the time of the Spanish conquest" in the 16th century.

Lennon's announcement, reported on Page 1 in the Feb. 1 editions of The Washington Post and The New York Times and prominently elsewhere, did not claim the discovery of the site -- he gave credit to "a Peruvian expedition" in the 1960s. But the announcement suggested that the site had faded into obscurity after that expedition completed a brief visit.

In fact, it has been the subject of dozens of books, magazine and newspaper articles, and even a 1970 CBS News documentary on Andean archeology. Many of the writings were by Douglas Eugene (Gene) Savoy, a U.S. explorer who discovered the site in a 1964-65 expedition and named the cluster of 18 buildings Gran Pajaten.

"I don't understand why they made such a big deal out of this," Betty Meggars, a specialist in South American archeology at the Smithsonian Institution, said. "The Peruvian highlands are filled with ruins all the way from Machu Picchu 500 miles to the south on up."

Savoy, who said he found 39 other ruined cities in the Gran Pajaten region, believes that all were part of a civilization, the Chachapoyas, conquered by the Incas.

"I don't deny anything Gene Savoy says," Lennon said, "but I do take exception to the idea that there's nothing left to do at Gran Pajaten because he did it all. Gene discovered the site. What we want to do is study it in a lot more scientific detail than has been done so far." He said there had been no exaggeration nor intent to deceive in his announcement about the site.

Another issue on which deeper study of the site may shed light is the demise of the Inca empire, which Lennon believes conquered the people of Gran Pajaten.

Although, officially, the Spaniards conquered the Incas, archeologists have suspected that the empire was in decline and disarray before the conquistadors arrived. How else, they ask, could Francisco Pizarro and a few hundred soldiers have destroyed a once militarily strong empire of 6 million people?

Various factors have been suggested. Shortly before the Spaniards' arrival the Incas suffered a devastating civil war, and there is evidence that epidemics of smallpox, introduced by the Spaniards on a previous visit to Peru, had swept into the Inca highlands ahead of the conquistadors. Human remains, which Lennon believes are inside sealed tombs at Gran Pajaten, may show evidence of smallpox.