Petra is spectacular. While it may not be as architecturally intricate or historically interesting as somewhere like Ephesus or Pompei, the setting, and the way the city is carved to the rock makes this without doubt the most beautiful ancient site I have ever been to. The city is cut out of the sides of a rift valley, formed by tectonic movements below. The valley is an amazing site on it's own and would be worth visiting even if a city had not been carved out of it's walls.
Petra's unusual geography forced it to be long and thin. It is around three miles from end to end. A network of horse, donkey, and camel operators offer to ferry around those who are too old, infirm, or fat to do the hike themselves.
The weather was pretty hot and a lot of people seemed to be succumbing to the heat and resting to drink in the shade. I think I benefitted from my past three weeks in Iran and Turkey acclimatizing to desert. As one person told me in Cappadocia: desert heat is like a hot curry: If you fight it you will fail; you have to just accept it.
The most famous site in Petra is a building known as "the treasury" which is actually a tomb. This building was made famous by Indiana Jones and the Last Crusade, and it is every bit as spectacular as the movie suggests. Sadly a barrier stops people entering, but that is probably for the best as, if the movie is to believed, it is apparently filled with whirling blades of death.
The second most famous site in Petra is "the monastery", which is also a tomb, and looks exactly the same as the treasury. The monastery is high up at the top of the cliffs and the hike up to the top is really fun.
As one would expect, Petra is filled with tourists. It felt weird to be surrounded by western tourists after weeks in Iran where there were almost none. It also seemed that some of the things the Jordanians had done to make Petra tourist friendly detracted from the site. The valley floor was concreted over, there were shops everywhere, and there was a fancy restaurant at the end. At times it felt more like "Petra Las Vegas" than "Petra".