The Nabateans (descendents of the Biblical Edomites) controlled and taxed virtually all trade from the East to Europe and Africa. Virtually all trade routes led through the narrow canyon of The Siq and into their capital city, Petra, therefore they were vastly weathly as well as heavily influenced by many cultures. This is why the blend of architecure in Petra's monuments is so bizarre and stunning.
Petra was founded and most monuments were carved or built in the 2nd century AD. However, by the 7th century, alternate trade routes had developed and Petra was abandoned and faded into antiquity.
European archaelogists studying the Near East had, for decades, longed to find the location of the ancient Nabatean capitol. Every other ancient civilization's capital had been discovered save this.
With that in mind, in the year 1812, Swiss explorer John Burkhardt deviated from his intended exploration of Sudan in search of Petra. Finding the native Bedouins hostile to outsiders, he dressed himself as a pilgrim Muslim and hired a Bedouin to take him to a holy mountain to make a sacrifice.
The Bedouin led him through the narrow twisting canyon of The Siq and then out across the valley of Petra where Burkhardt became the first westerner to see the vast carved monuments in over 1000 years.
But, as the Bedouins feared the evil monuments, Burkhardt could not comment on them or attempt to explore them. He documented and sketched them on a notepad hidden beneath his cloak.
After news of the discovery reached Europe, tourists began to make the long trek to see the ancient city, and thus the "Rose Red City half as old as Time" once again was populated by a powerful and influential culture, this time European in origin.