El-Muthlim tunnel

The water diverted by the dam passed along an excavated- that can be clearly seen carved into the rock- channel close to the left-hand cliff until it disappeared down a tunnel specially dug for that purpose. The tunnel is worth spending a few minutes looking at for it is an important example of the Nabataean brilliance in water engineering. It would probably have been made at the same time as the original dam. El-Muthlim tunnel has a particular importance because the Semitic name of Petra, Reqem (Nabataean Raqmu) was engraved on the walls of it and was found through cleaning.