NEW YORK, NY.- Archaeologists in Bulgaria made an unexpected discovery in an ancient Roman sewer last week: A well-preserved marble statue, taller than a man.

“We found it by accident,” said Lyudmil Vagalinski, scientific director of the excavation. “It was amazing. A whole statue appeared in front of us.”

The discovery could illuminate how people in the area, modern-day Bulgaria, fought to preserve their religion as Christianity swept across the ancient world. The sewer may have been a hiding place used by pagans trying to protect the imposing statue from Christian zealots, who sometimes destroyed the heads of pagan deities.

They seem to have succeeded: Researchers have not yet unearthed the entire statue, but the face and head show no signs of destruction.

“It’s a miracle that it survived,” Vagalinski said.

He and his colleagues were working on a routine dig near the village of Rupite, close to Bulgaria’s southwestern border with Greece, in the blistering summer heat last week when they spotted marble in the soil.

They tried to keep their excitement in check, Vagalinski said, as a marble foot emerged. Then, they saw careful carvings on the toenails. Legs sprouted upward. A torso followed. Finally, a head.

“It was just waiting for us,” he said. Almost as if the statue had found them, not the other way around.

This would not be the first ancient statue to emerge from an unsavory trench: Construction workers in Rome also found a marble figure in a sewer system last year.

The Bulgarian statue — which Vagalinski thinks may depict the god Hermes — may have been buried in the late fourth century. He thinks it was placed in the sewer a few years after 380 A.D., the year Emperor Theodosius I declared Christianity the official religion of the Roman Empire.

The pagans in the ancient city where the statue was found, then called Heraclea Sintica, may have wanted to protect their treasures from Christian defacement.

“They tried to secretly preserve their memory of these deities,” Vagalinski said.

He also thinks that the statue may have been buried some time after 388 A.D., when a major earthquake hit the area and devastated the city. It appears to have destroyed infrastructure to such an extent that the sewers were no longer functional, he said.

But even though the sewer had been decommissioned following the quake, Vagalinski added, it remained sturdy, and became something of a burial ground for pagan history.

“Although we might not think a sewer is the right place, at least it would be unharmed,” said the Rev. professor Martin Henig, an expert on Roman art at Oxford University who was not associated with the dig. “Nobody was going to touch the sewer,” he added.

The statue is missing part of its right arm, which almost looks like it was amputated, Vagalinski said. The left hand may be damaged, too. But otherwise, the statue seems mostly intact.

“It is rare and exciting to find an almost perfectly intact statue, and especially one of such apparently high quality,” Elizabeth Marlowe, director of the museum studies program at Colgate University, who was not involved in the dig, wrote in an email.

The statue’s geographic location may also offer insights to researchers. Many such well-preserved statues were looted, Marlowe wrote, and “surface seemingly out of thin air in dealers’ shops in Switzerland or New York.”

This can mean that the finds — although remarkable — are often stripped of clues about their origins. (Smugglers work hard to erase those details to obstruct cultural officials who may try to get artifacts back to the place they were found.)

“If this surfaced on the art market, we would never in a million years have guessed that it came from a small town in the Bulgarian hinterland,” Marlowe wrote. “We would have guessed that it came from a wealthy city or private estate in Italy.”

Such an impressive marble statue — which she said was a rare find in southwest Bulgaria — could be useful to understanding Heraclea Sintica. Marlowe said the city was not a well-known Roman site. “This has the potential to greatly enrich our understanding of the local culture of this region,” she wrote.

For now, Vagalinski and his team are focused on carefully extracting the statue. Once it is fully excavated, which he hopes will happen this week, he and other researchers will work to date and analyze the piece — before readying it for display in the local history museum.

“It’s like a sensation,” he said. “Such huge statues are very rarely found.”

This article originally appeared in The New York Times.