I got up early and was the first person in Petra. I even beat most of the Bedouins that foist over-priced trinkets and camel/horse rides on the tourists. For fun and $2 USD, I did take a horse the one kilometer to the start of the Siq, the 1200m narrow gorge that leads to the ancient site. Going down the Siq alone and in silence was otherworldly. And then, finally seeing the magnificence and grandeur of the Treasury suddenly appear was magical. If you don’t know, the Treasury is the building featured as the resting place of the Holy Grail in the Indiana Jones movie. The rooms inside are big, but not as cool as in the movie. It is much bigger than it looks. Check out the little people in the last picture.
Having only known about the Treasury, I was surprised at how extensive the ancient city of Petra was. It was big and quite grand. The buildings were carved out of the sandstone cliffs instead of being built by individual rocks. The skill of the sculptors is incredible. Huge columns and decorative elements that would have been hard to carve separately were all carved in place. Unfortunately, the elements have taken their toll and worn away most of the fine detailing on the structures. They are still very impressive. 
