The FBI was excited. That much seemed evident from the affidavit the agency lodged on March 9, 2018, asking a court for permission to dig up a Pennsylvania hillside in search of Civil War gold.

The affidavit related a story from a document titled “The Lost Gold Ingot Treasure,” which had been found in the archives at the Military History Institute, in Carlisle, Pennsylvania. The tale, in its barest bones, was this: In June 1863, a caravan of Union soldiers transporting a shipment of gold through the mountains became lost. Three men were sent to get help and eventually one returned with a rescue party, which located the group’s abandoned wagons but no men, no gold. Teams from the Pinkerton detective agency scoured the hills. In 1865, two and a half buried ingots were found, and, later, the bones of three to five human skeletons. The rest of the gold remains missing.

The affidavit also laid out how this story had come to the FBI’s attention. A treasure hunter named Dennis Parada had heard folklore alluding to the lost gold “since he was a child,” and had spent “over forty years” searching for it. Now he and a team including his son, Kem, believed they had finally located it.