They are generally concealed by later deposits, but are exposed to view along the eastern margin of the Wadi Araba, at the foot of the plateau of Edom.
From the `Araba travellers approach by a track which leads round Jebel Harun (Mt Hor) and enters the plain of Petra from the south; it is just possible to find a way in from the high plateau on the north; but the most impressive entrance is from the east, down a dark and narrow gorge, in places only to or 12 ft.
Shrinkage caused the pelagic limestone bottom to be upheaved in two ridges, between which occurred a long fracture, which can now be traced from Coelesyria down the Wadi Araba to the Gulf of Akaba.