(NEXSTAR) -- Archaeologists have unearthed a hidden tomb containing the remains of 12 ancient skeletons at the historic site that served as one of the filming locations for the 1989 blockbuster "Indiana Jones and the Last Crusade." The discovery was made earlier this year beneath the iconic Treasury building in Petra, Jordan, a "lost city" named one of the New Seven Wonders of the World. It was recently featured in the season premiere of the Discovery Channel's "Expedition Unknown," according to a news release. The Treasury, also known as Al Khazneh, is a rock structure that was hand-carved by the Nabataean Kingdom more than 2,000 years ago, as noted by the Smithsonian Magazine. It's one of Petra's most famous and visited monuments. This file photo shows The Treasury, also called Al Khazneh, in Petra, Jordan. (Getty Images) While the site has long-fascinated visitors, its true purpose has remained a mystery, the release stated. This prompted a team of American and Jordanian researchers, led by Professor Pearce Paul Creasman from the American Center of Research, to start digging. The ancient tomb they found beneath the surface not only contained skeletal remains, but a trove of artifacts made from bronze, iron and ceramic, CNN reported. Baby born in Michigan brewery’s parking lot given appropriate middle name "We were absolutely stunned by the revelation of this hidden chamber," said adventurer Josh Gates, of "Expedition Unknown," in a statement. "Since nearly all of the tombs at Petra have been found empty, this is perhaps the most significant tomb ever found at Petra and a discovery of historic proportions," he added. A team of American and Jordanian researchers uncovered a hidden tomb beneath the Treasury in Petra, Jordan. (Courtesy of Discovery's Expedition Unknown)A team of American and Jordanian researchers uncovered a hidden tomb beneath the Treasury in Petra, Jordan. (Courtesy of Discovery's Expedition Unknown) One skeleton in particular was found holding a ceramic vessel that "looked nearly identical to the Holy Grail featured in 'Indiana Jones and the Last Crusade,'" Gates said. But upon further examination, the vessel turned out to be the top part of a broken jug. Petra has been a UNESCO World Heritage Site since 1985. The Nabataeans were known for their advanced water management systems, such as dams and aqueducts, as well as their unique architectural style, according to UNESCO. Gates said the recent tomb discovery could help researchers learn even more about the daily lives of the early Nabataeans and the Treasury.