Stretching 70km from the Desert Hwy to the Dead Sea is the vast Wadi Mujib, proudly called the ‘Grand Canyon of Jordan’. The spectacular chasm is also significant as the historic boundary between the ancient Amorites (to the north) and the Moabites (to the south). Moses is believed to have walked through Wadi Mujib, then known as the Arnon Valley. The King’s Highway crosses the wadi's upper reaches, while its lower reaches fall within the Mujib Biosphere Reserve – normally accessed from the Dead Sea Hwy.
The canyon measures 1km deep and 4km wide, but it takes the King’s Highway 18km of road to switchback down one wall of the wadi, across the dam at the bottom and up the other side. From the picturesque olive groves of the upper plateau, on either side of the wadi, there's no hint of the upheaval that splits the land in two.