The mystery veil on the Treasury Monument in Petra, Jordan has been lifted again.

Under the ancient rock-cut structure, archaeologists discovered a tomb that contained 12 human skeletons in a relatively good state of preservation along with a large number of grave offerings.

The discovery was made more than 20 years after tombs similar to this one were discovered on the other side of the famous Treasury, known also as Al Khazneh. This is a UNESCO World Heritage Site and one of the Seven Wonders of the World.

Early this year, Jordanian authorities granted permission to a team of researchers to conduct a week-long remote sensing around the Treasury. The Treasury was the heart of a city that the Nabatean Kingdom had carved into the walls and canyons of the desert.

Richard Bates said that there was a constant thought that more tombs might exist, but that none of them had been discovered with burials still inside. The hope was to discover a tomb intact.

The joint Jordanian-American team, including the Jordanian Department of Antiquities, and the American Center of Research (a nonprofit in Amman), detected and located a void using ground-penetrating radio waves. Bates explained that instead of digging down straight, which would have required cutting through solid rock, the team dug from the outside toward the void.

In the jar, 12 human skeletons were found at the original burial site. One of them was holding the top portion of a broken glass jug dating back to the 1st century BC. Bates said that the remains are likely to include men and women, and they range in age between children and adults.

The discovery may provide new insights into the Nabatean culture and the purpose of the Treasury.

Bates stated, “Since no complete burials have ever been discovered here before, we are likely to learn a lot more about the Nabatean Kingdom from this discovery.”

The Treasury is one of Petra’s most iconic monuments. It receives over a million visitors each year. In Steven Spielberg’s 1989 movie “Indiana Jones and the Last Crusade”, it was the resting place for the Holy Grail.

Discovery Channel aired a two-part documentary on the excavation of this newly discovered tomb.

Bates stated that there are indications of other voids around the area which could be tombs.

He said that it was highly likely there were more fossils to be discovered. “We need funding to go back and continue our studies.”