I made my second trip to Jordan in October 2018.  From the middle of the seventh century until the middle of the eighth, the Umayyad dynasty built several desert castles in what is now northeastern Jordan, which represent some of the most impressive examples of early Islamic architecture.  I visited Qasr Amra and Qasr Al-Kharanah, two of the best known desert castles — but inexplicably only the former has been inscribed on the list of World Heritage Sites. I also visited Umayyad Palace on the Citadel Hill of Amman, from where all of hazy Amman could be seen.