The ancient city of Petra, located in the heart of the mountainous desert of southern Jordan, had different approaches in the past. One possible route was from the south, across the plain of Petra and around Jabal Haroun or Aaron's Mountain. Another approach was from the high plateau to the north. But modern visitors approach Petra from the east, through a narrow gorge called the Siq, that ends dramatically in front of the elaborate ruins of the “Treasury” or Al-Khazneh in Arabic.
The Siq is not really a gorge because it was not formed by water erosion but by tectonic forces that caused the sandstone mountain to split in half creating a deep, narrow pathway. Later, water from flash floods gradually rounded the sharp edges of the gorge into smooth curves.
The entrance to the Siq once contained a monumental arch, but it collapsed in 1896 following an earthquake. Only the two abutments and some hewn stones of the arch remain.
The path through the Sig meanders for 1.2 km between beautifully-colored sandstone cliffs that tower 150 meters on either side. The Siq is no more than 3 meters wide on average, but occasionally the path widens enough to allow in warm sunlight and even a tree. In other places, it becomes so narrow that one can touch both walls with arms outstretched.
Along the way are several archaeological artifacts such as ancient water aqueducts that run along the sides of the canyon and brought water down to the center of Petra. Small niches are carved out of the rock, high up the ground and can only be accessed by stairs. There are also remnants of what must have been large and impressive statues. Along the Siq are also some underground chambers, whose function is not clear. It’s thought that they housed the guards that defended the main entrance to Petra.
As one approaches the end of the Siq, a thin sliver of the Treasury comes into view through the narrow opening. Upon exiting the Siq, visitors can have full view of its jaw-dropping grandeur.
The Treasury was originally built as a mausoleum and crypt, but legend of it containing ancient riches had earned it its current name. The loot was rumored to be hidden inside a stone urn high on the second level. Local Bedouin tribes had tried to test the theory by shooting at the urn in hopes of breaking it open and spilling out the "treasure”. But the decorative urn is, in fact, solid sandstone. Its façade is now riddled with bullet holes.