The island would go on to receive scores, if not hundreds, of people who died during the AIDS epidemic, which during the 1980s and 1990s killed more than 100,000 people in New York, about a quarter of AIDS deaths nationwide during the same period.

Trying to pin down the precise number of those with AIDS buried on Hart Island is difficult. A longstanding stigma about the island and criticism that the burial practices are crude and outdated have made city officials reluctant to provide many details. Officials at several city agencies involved in the burials refused interview requests to discuss the issue and insisted that no data or any other information was available on AIDS burials.

But piecing together an estimate is possible by surveying the many hospitals that treated AIDS patients during the epidemic and sent bodies to potter’s field. By that accounting, the number of AIDS burials on Hart Island could reach into the thousands, making it perhaps the single largest burial ground in the country for people with AIDS.

It is an untold chapter of the AIDS crisis, but in recent years some of the island’s secrets have started to tumble out largely because of the work of a longtime activist whose legal pressure has wrested information from the city, giving relatives of people with AIDS answers they have long sought.

One of them, Elsie Soto, 35, of the Bronx, learned recently that her father, Norbert Soto, who died in 1993 from AIDS, is buried on the island.