Petra

Petra is an ancient rock cut city in the Ma'an Governorate of southern Jordan, known to its Nabataean inhabitants as Raqmu. The Nabataeans used efficient rainwater collection and desert farming to survive and built Petra into a major regional trading center, reaching an estimated population of 20,000 in the 1st century AD when the famous Al-Khazneh structure was likely built as a royal mausoleum; the city was absorbed into the Roman Empire in 106 AD as part of Arabia Petraea and gradually declined as sea trade routes emerged and a devastating earthquake in 363 AD damaged its water systems.