https://en.wikipedia.org/wiki/Palmyra_Castle

Palmyra Castle, also known as Fakhr-al-Din al-Ma'ani Castle (Arabic: قلعة فخر الدين المعني) or Tadmur Castle, is a castle overlooking Palmyra in the province of Homs, Syria.

The castle is thought to have been built by the Mamluks in the 13th century[ on a high hill overlooking the historic site of Palmyra, and is named for the Druze emir Fakhr-al-Din II, who extended the Druze domains to the region of Palmyra during the 16th century.

The site of the castle and Palmyra in 1980 became a UNESCO World Heritage Site in recognition of the monumental ruins of a great city, which was one of the most important cultural centres of the ancient world. The site was designated a national monument in Syria and a buffer zone was established in 2007.

The castle lying on raised bedrock was a well defended position for a fortification with thick and high walls, which was also surrounded by a moat that had only one access available through a drawbridge.

The historic site was placed on the list of World Heritage Sites in Danger in 2013 due to the ongoing Syrian Civil War