The Treasury (or El-Khazneh) features the famous intricately carved facade filled with Nabataean gods and characters from myths, such as the Medusa heads, the horse-like figures of Pollux and Castor, winged Victories and dancing Amazons. There are 800 such individual monuments, and you will have the time of your life exploring the streets lined with temples, arched gateways, buildings, baths, tombs, and funerary halls. What's even more amazing is that more of these were carved from the sandstone. The grounds in front of the famous façade of El-Khazneh also served as an Indiana Jones filming location (Indiana Jones and the Last Crusade).
Also, in the courtyard, you will find the Bab Al-Siq Triclinium and the Obelisk Tomb. The Triclinium is a rock with rooms carved into it and benches placed at its interiors. The city features the Street of Facades meanwhile, the Theater (which seats 3,000 people), and the Royal and Urn Tombs. The Royal Tombs house what are believed to be Nabataean kings, while the Urn Tomb has small niches that lead to burial chambers.
The city center
At the center of the archeological complex, you can find the Nymphaeum remnants (a public fountain dedicated to water nymphs), the Colonnaded Street, which leads one through to the Temple of the Winged Lions. At the end of Colonnaded Street, you will also find a ceremonial entrance to the Qasr Al-Bint Temple called the Arched Gate. This gate is of Greco-Roman design.
Qasr Al-Bint Temple
With its massive walls (23 meters high!), this is the most important temple at the Petra and is built in honor of Dushara (later to become Dionysus, the Greek God of wine). It has three rooms with a stone god block.
For more on the Nabataeans culture, you can also look at the Al-Habees, which is a museum and the Habees High Place. Climbing up on further, you will find the High Place of Sacrifice, which is to be found on top of Attuf Ridge. There is still a host of monuments and buildings you can look into.