There’s long been speculation of underground chambers below the monument known as the Khaznah, or the Treasury, in the ancient city of Petra, Jordan — and now it’s been confirmed. Archaeologists recently discovered a tomb with at least 12 human skeletons and artifacts,

Archaeologists and Discovery Channel host Josh Gates found a secret tomb in Petra, Jordan, where the remains of 12 people were unearthed for the first time.

By the time Dr. Richard Bates swept his radar device over the sandstone of Petra’s ancient Treasury building, it had been more than two decades since anyone had so deeply probed the stone city’s grounds.