A monumental ’nest’ at the height of 900 meters above sea level is hidden in the rocks. The masters had to show remarkable patience, turning the rocks into the masterpiece of Petra. So, at the end of the cool Siq canyon, there opens a fantastic view of the facade with columns and porticos — Al-Khazneh (the ’treasury’ in Arabic). It is said to be a temple or a mausoleum. The problem is trying to understand how the carvers worked. After all, it’s impossible to create such a work without scaffolding, but they didn’t know about it yet.