Climb to the High Place of Sacrifice or the Monastery
These are two of the highest points in Petra but are easily accessible, as long as you are reasonably fit, and offer the reward of wonderful views. The high place of Sacrifice involves a 30-40 minute climb.
Reaching the Monastery demands some hard climbing, but the reward is worth it when you can see one of the reward is worth it when you can see one of the largest monuments in Petra with a 50-meters square façade. Form this lookout point; you have unbeatable views of the Petra basin and Wadi Araba.