Last summer, archaeologists and a metal detectorist conducted a small survey of the tumulus on behalf of the Norwegian Directorate for Culture Heritage.

The stones, or menhirs — some as tall as six feet — buttressed a massive capstone set in a tumulus, or a mound of earth and pebbles.

The call sounded from far away, and Wart found himself standing by the side of an ancient tumulus, like an enormous mole hill, with a Mack hole in front of him.

Bassett said he was sitting on a pile of boulders when he realized that the rocks were the top layer of a tumulus, an archaeological term for a burial chamber or sepulcher.

It's possible, he said, that when pyramid building came into fashion at Sedeinga it was combined with a local circle-building tradition called tumulus construction, resulting in pyramids with circles within them.