Petra (meaning: "rock") is a historic and archaeological city in the Jordanian governorate of Ma`an that is renowned for its rock cut architecture and water conduits system. It is the most famous symbol of Jordan as well as it`s most known tourism attraction. It lies 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. Petra is also one of the New Seven Wonders of the World. The Nabataeans constructed it as their capital city around 100 BCE.
Pliny the Elder and other writers identify Petra as the capital of the Nabataeans, Aramaic-speaking Semites, and the centre of their caravan trade. Enclosed by towering rocks and watered by a perennial stream, Petra not only possessed the advantages of a fortress, but controlled the main commercial routes which passed through it to Gaza in the west, to Bosra and Damascus in the north, to Aqaba and Leuce Come on the Red Sea, and across the desert to the Persian Gulf.
The end of the Siq, with its dramatic view of Al Khazneh ("The Treasury").Excavations have demonstrated that it was the ability of the Nabataeans to control the water supply that led to the rise of the desert city, creating an artificial oasis. The area is visited by flash floods and archaeological evidence demonstrates the Nabataeans controlled these floods by the use of dams, cisterns and water conduits. These innovations stored water for prolonged periods of drought, and enabled the city to prosper from its sale.
The TheatreAlthough in ancient times Petra might have been approached from the south via Saudi Arabia on a track leading around Jabal Haroun ("Aaron`s Mountain"), across the plain of Petra, or possibly from the high plateau to the north, most modern visitors approach the site from the east. The impressive eastern entrance leads steeply down through a dark, narrow gorge (in places only 3–4 m (9.8–13 ft) wide) called the Siq ("the shaft"), a natural geological feature formed from a deep split in the sandstone rocks and serving as a waterway flowing into Wadi Musa. At the end of the narrow gorge stands Petra`s most elaborate ruin, Al Khazneh (popularly known as "the Treasury"), hewn into the sandstone cliff.
El Deir ("The Monastery").A little further from the Treasury, at the foot of the mountain called en-Nejr, is a massive theatre, so placed as to bring the greatest number of tombs within view. At the point where the valley opens out into the plain, the site of the city is revealed with striking effect. The amphitheatre has been cut into the hillside and into several of the tombs during its construction. Rectangular gaps in the seating are still visible. Almost enclosing it on three sides are rose-colored mountain walls, divided into groups by deep fissures, and lined with knobs cut from the rock in the form of towers.