Just days after archeologists on Maryland's eastern shore uncovered what they believe to be the oldest settlement of African-Americans in the United States, another team in Philadelphia unearthed what may be the resting place of nearly 3,000 others under a playground in the city's Weccecoe Park.

On Thursday, Douglas Mooney, senior archeologist for URS corporation and his colleagues dug up a single white gravestone belonging to 26-year-old Amelia Brown, who was likely a member of the Mother Bethel A.M.E. Church, who bought the burial site as a private cemetery in 1810 and used it as such until 1864.

Mother Bethel is the oldest African-American church in the country, researchers say. During the late 18th century, cemeteries within Philadelphia's city limits would not accept Black people, which prompted the congregation to purchase the plot near Fourth and Queen streets.

During a dig at the playground last week, a team of archeologists broke the asphalt in four places at Weccecoe Park, looking for clues as to where the cemetery limits are, and how far down, NBC Philadelphia reports. The dig took them three feet down, revealing evidence of grave shafts and stone walls representing the border of the cemetery.