Petra "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 Nabateans constructed it as their capital city around 100 BCE.
The site remained unknown to the Western world until 1812, when it was introduced to the West 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.