Petra was a city oasis spectacularly situated between the mountain cliffs of southern Jordan desert , and almost halfway between the Dead Sea and the Gulf of Aqaba . Its inhabitants , the Nabataeans , Petra settled over 2000 years ago . Its prosperity was due to trade caravans as different routes converged at this oasis , trade of India and Arabia came to the Red Sea through Petra before reaching the Mediterranean and the routes from Mesopotamia and Petra crossed East way to Egypt. Despite the growing power of Rome in the West, the Nabataeans were able to remain independent until 106 AD , when the Emperor Trajan Petra became a Roman province . The place was so remote and inaccessible , which was unknown since the time of the Crusades until the nineteenth century that a Swiss J. Burckhardt , disguised as Arab sheik and accompanied by a Bedouin guide visited the city . Taking secret notes and sketches, wrote : "It seems quite likely that the ruins are there in Wadi Musa Petra the ancient dela " . Despite Burckhart rediscovery , it was not until 1924 when the first archaeological excavations were conducted in Petra , under the supervision of the British Archaeological School in Jerusalem. Groups Jordanian and foreign archaeologists have brought to the surface several areas of the city , revealing much data on the life of its former inhabitants. A large part of the attraction of Petra comes from its spectacular position in a narrow gorge . From the main entrance you can walk down the Siq gorge , and cut through the cliff walls , watching his step betilos with ancient inscriptions and rock carved dwellings . The Treasury, Petra's most famous monument suddenly appears at the end of the Siq . Used in the final scene of the film "Indiana Jones and the Last Crusade" , this huge facade is just one of the first secrets of Petra . Several trails and climbs reveal hundreds of buildings , facades , tombs, baths ... On top of a mountain and overlooking the city , is the Tomb of Aaron , brother of Moses.