Description Petra (from petra-πέτρα; cleft in the rock in Greek; Arabic: البتراء, Al-Batrāʾ) is an archaeological site in the Arabah, Ma'an Governorate, Jordan, lying on the slope of Mount Hor in a basin among the mountains which form the eastern flank of Arabah (Wadi Araba), the large valley running from the Dead Sea to the Gulf of Aqaba. It is renowned for its rock-cut architecture. Petra is also one of the new wonders of the world.The site remained unknown to the Western world until 1812, when it was discovered by Swiss explorer Johann Ludwig Burckhardt. It was famously described as a rose-red city half as old as time in a Newdigate prize-winning sonnet by John William Burgon. UNESCO has described it as "one of the most precious cultural properties of man's cultural heritage. In 1985, Petra was designated a World Heritage Site.The Monastery, Petra's largest monument, dates from the first century BC. It was dedicated to Obodas I and is believed to be the symposium of Obodas the god. This information is inscribed on the ruins of the Monastery (the name is the translation of the Arabic Ad-Deir).