– Hundreds of U.S. Navy officers and sailors have lain for decades under the anonymity of inscrutable gravestones at Mount Moriah, a 19th-century cemetery here. For many of the dead, time wore away their names. For others, long-ago conflicts stole not just their lives but their identities, rendering them “unknown” — though not, as it turns out, for eternity.

About 250 volunteers invested nearly a thousand hours over four years to identify 718 veterans buried in the Naval Plot, one of two sections within Mount Moriah that are part of the National Cemetery Administration and reserved for veterans and their families.

“These men and women had a name when they went into the service, whether they fought a war or stayed home, whether they served a day or 30 years. They had a name,” said Paulette Rhone, board president of the Friends of Mount Moriah Cemetery.

Now, nearly two years after the project ended, cemetery officials and relatives of those interred there are urging the federal government to replace the old stones with new ones, engraved with the names recovered by the volunteers.

National Cemetery Administration officials say it will take time. “We want to make sure we’ve done our due diligence and ensure accuracy,” said Gregory Whitney, who oversees Mount Moriah’s military plots for the Department of Veterans Affairs.

The agency’s historians are researching burial records and other historic information about the graves. When that task is completed, Whitney said, the VA will replace the stones. Each will reflect the marker’s original design. Whitney said he expects the work to start next spring.

In April 2011, Mount Moriah, once the resting place of Betsy Ross’ remains, was closed. Volunteers began weekly visits to a storage facility — and later to city archives, where records were moved — to photograph every cemetery document in 300 boxes.

But by the summer of 2013, no registry had been found with the names and locations of those buried in the cemetery. About 200 students from Villanova, Drexel and Temple universities volunteered to walk the rows and record the information on more than 2,000 stones. They found hundreds of markers that were worn to illegibility or inscribed “Unknown.”

Then, in December 2014, one of the 300 storage boxes gave up Mount Moriah’s secrets. Inside were seven large binders containing the elusive burial records.