Serabit el Khadim
Serabit el Khadim is the most important Pharaonic ruin in the Sinai featuring the only temple outside of mainland Egypt, on the flat top of a small range. The easy climb starts at the end of the asphalt road in the settlement of the same name. You find several mines on the plateau as well as the Temple of Hathor, and get spectacular views on the desert belt and the Tih Plateau. You could descend on the other side at Umm Ajraf, convenient if you carry on to El Ramla or Wadi Mukattab.
