In a pine forest north of St. Petersburg, investigators have discovered a mass grave of victims of Joseph Stalin's 1937-38 purges. More than 1,100 people, many of them among the elite who disappeared during the Great Terror, were shot and buried at the site.

The discovery came after a search that lasted nearly a decade. The location was pieced together from clues found in archives of the former KGB secret police and its forerunner, the NKVD.

"That grave has tremendous significance -- these are representatives of the elite of that time, who just disappeared," said Venyamin Yofe of the St. Petersburg chapter of Memorial, a group dedicated to uncovering the truth of Soviet-era crimes, including the deaths of millions in Stalin's system of labor camps known as the Gulag.

Among those executed at the site, he said, were four Russian Orthodox archbishops, 30 Catholic priests, 300 Ukrainians including prominent nationalists and intellectuals, 20 Tatar political figures, a Gypsy king, Belarusan leaders, and many St. Petersburg literary and scientific figures, as well as factory and shipyard workers.

While it is known that 1,111 prisoners were executed, it is possible that the number of victims buried there is far larger, because the bodies of executed prisoners among slave laborers who built the White Sea canal in the '30s may also be there.

The mass grave is not the first to be found since the collapse of the Soviet Union. Many of the secrets of the Soviet era have begun to seep out of archives, although the work is often slow and painstaking. The discovery of the new mass grave -- in Sandormokh, about 243 miles north of St. Petersburg -- underscores the difficulty.

Stalin's purges of 1937-38 sent millions to labor camps and to their death. At the Sandormokh site, the killings were carried out at the peak of the purges, between Oct. 27 and Nov. 4, 1937, Yofe said.

Yofe said the Memorial group, including local chapters in the region, had been searching for this site since 1988. Many of those killed were prisoners brought from the Solovetsky Islands prison camps on the White Sea, one of the most notorious in the Gulag. Last year, sifting through records of the former KGB, investigators got a complete list of 1,111 prisoners who were executed, but they had little information about where.

Then they found the records on the case of Capt. Mikhail Matveyev, who had been specially assigned from a branch of the secret police in what was then Leningrad to oversee the execution of the prisoners. His records included a report dated Nov. 10, 1937, that the prisoners' execution had been carried out. Later, Matveyev was arrested.

His records included a mention of the execution site in the Karelia region near the border with Finland. They said was at the 16-kilometer mark on a road between the towns of Medvezhyegorsk and Povenets. Witnesses described the execution site as a large sand pit.

After much searching, the investigators found it on July 1. It was not far from where Matveyev's records had indicated, but since the highway had changed it was at the 19-kilometer point. The investigators spotted small pits that looked unnatural -- and found skulls pierced by bullet holes. The victims usually were shot in the back of the head.

The opened graves were closed on July 2. A monument is to be erected in October.