A Nabataean ritual platform on top of Jebel al-Madhbah, the long ridge above the main valley. The climb is roughly 800 steps, similar to the Monastery but on the opposite side, and the route can be done as a circular walk down the back of the mountain through the Wadi Farasa, past tombs and a small Roman soldier's tomb facade.
At the summit are two obelisks cut from the live rock — the surrounding stone was simply removed to leave them standing — and a flat ceremonial enclosure with altar, drains, and a basin. The view is the real reward: the whole basin of Petra spreads below, the Royal Tombs in their cliff and the Monastery on its distant ridge both visible from up here.