The Nabateans were a semi-nomadic tribe from northern Arabia who developed an Empire centered in modern-day Jordan between the 3rd century BCE and the 2nd century CE.  Records of their empire can be found from China to Rome and their cities were in modern Jordan, Israel, Syria, Yemen, and Saudi Arabia.

I plan to someday visit the Nabatean city of Madin Saleh, which is in Saudi Arabia.  If you have been there, know anything about it, or know someone who has, please contact me.