For decades, an unmarked cemetery sat undisturbed, tucked away at the edge of a Florida high school campus.
But last week, Hillsborough County school district officials announced that the burial ground had been found with help from ground-penetrating radar scans. The radar bounced back with evidence of about 145 coffins, buried just a few feet beneath the surface.
The discovery of what appears to be the Ridgewood Cemetery, where mostly African-Americans were buried in the 1940s and 1950s, on what are now the grounds of C. Leon King High School was a sad but important reminder of the city’s suppressed history, said Yvette Lewis, the president of the county branch of the N.A.A.C.P.
“The city of Tampa — and Hillsborough County itself — has pretty much erased and eradicated African-American history,” she said. “Now we feel as though our ancestors are coming back and talking to us and saying, ‘Hey, tell our story.’”
Ms. Lewis is on a historical response committee that convened to investigate and respond to the rediscovery.
Ridgewood could be the second predominantly black cemetery to be rediscovered in the city in recent months. And it might be only the beginning as district, state and military officials make plans to devote more resources to uncovering burial sites that have long been ignored.
[“No longer forgotten”: Ohio students had a headstone made for black settlers.]
The Hillsborough County School Board said in a statement last week the radar had probably missed some of the graves, since historical records show more than 250 people could have been buried at the site, up to 77 of which might have been children and infants.
Another burial site made headlines just a few months ago after a tip from a Tampa resident — Ray Reed, a retired county employee — led journalists at The Tampa Bay Times to investigate Zion Cemetery, the first African-American cemetery recognized by the city, in which hundreds of people were thought to have been buried. The land had since been occupied by restaurant warehouses and public housing.
Mr. Reed also raised awareness about the possibility of the burial site at King High School, Ms. Lewis said.
Another investigation is set to take place at MacDill Air Force Base in Tampa. A spokesman there said that historians had pointed to a potential burial site at the base and that “resources are being allocated to examine the speculated area to confirm or dismiss” the possibility that a burial site lies there, too.
Questions about unmarked graves in Florida are not confined to Tampa. In June, State Senator Janet Cruz and the Senate minority leader, Audrey Gibson, both Democrats, announced that they were drafting legislation to form a task force to identify unmarked African-American cemeteries.
“This discovery at King High School is another example of how we must all work together to honor and memorialize every person who has contributed to Florida’s history, and particularly those who historically have been forgotten,” Ms. Cruz said in a statement on Tuesday.
Similar investigations are taking place outside the state. City officials in Tulsa, Okla., have used radar to find graves that date to a massacre in 1921, when a white mob rampaged through a black business district in a spate of violence that killed up to 300 people and destroyed more than 1,200 homes.
And across the United States, there have been fights to preserve historical black cemeteries that have plainly visible headstones but have been abandoned, neglected or threatened by development or gentrification.
“There have been a lot of these rediscoveries of late, but it’s because people are looking now,” said Rodney Kite-Powell, a historian at the Tampa Bay History Center. “People weren’t looking before, and technology has made it a lot easier to do this research, and it can be done so much more quickly than in the past.”
Mr. Kite-Powell said he had been following news of rediscovered graves in the area since last year, when reports emerged about possible remains from an 1830s-era cemetery in downtown Tampa.
“Tampa is a pretty old city by Florida’s standards,” he said. “We have a lot of things that have been built over, and many of those are cemeteries.”
Mr. Kite-Powell described the Ridgewood site as an indigent cemetery. “At that time, the city was still responsible for burying those who were too poor to afford funeral services anywhere else,’’ he said.
In 1957, the city sold the property to a group of private investors, who sold it to the school district two years later, Mr. Kite-Powell said, adding that the school district was aware of the burial site at the time.
King High School opened in northeast Tampa near the Hillsborough River in 1960, with nearly a thousand students. The county’s schools were still segregated despite the Supreme Court ruling that had struck down the practice in 1954, and a federal lawsuit accused the school board of delaying desegregation.
“Sometime from 1960 to now, the location and existence of the cemetery was forgotten,” Mr. Kite-Powell said.
But after getting a tip from Mr. Reed in October, the district hired a team of geophysical technicians from GeoView to scan and map areas on campus.
School district officials fenced off the area where the graves were found, on a corner of the campus that was home to agricultural lab facilities. Technicians marked the burial area with small pink flags.
The Hillsborough County school district said in its statement it had delivered the findings of the radar scan to the county medical examiner and state archaeologist last week, and they were expected to take 30 days to review the report.
“If the land is turned back over to Hillsborough County Public Schools, our leaders will work with members of the historical response committee to discuss proper ways to memorialize the individuals, how to best care for the space, and learning opportunities for students at King High School and other schools,” it said.
“The conversation has come up to memorialize the area,” Ms. Lewis said, adding that it should become “an educational moment for the kids to understand what happened, how it happened, and where we go from here.”
