Qal'at Ja'bar

Qal'at Ja'bar (Arabic: قلعة جعبر) is a castle located on the eastern bank of Euphrates Lake in Syria’s Raqqa Governorate. What was once a high hilltop looking over the Euphrates Valley is now an island in Lake Assad, reachable only by a man-made causeway. The hill may have been fortified as early as the 7th century, but the structures standing today were largely built by Nur ad-Din, who began rebuilding the castle in 1168. Excavations and restoration work have been ongoing since 1965. From 1921 to 1973, the castle was a Turkish exclave.

The hilltop’s earliest fortification date is uncertain. Before Islam, the site was known as Dawsar and sat along a route linking Raqqa to the west. In 1040/41, it was mentioned as Qal'at Dawsar when the Fatimid governor of Syria, Anushtakin al-Dizbari, campaigned in the area. Later, it came into the possession of Ja'bar ibn Sabiq, a member of the Banu Numayr or Banu Qushayr tribe, who was killed there in 1071/72. The castle gained a reputation as a refuge for Bedouin highwaymen from these tribes. In 1086, the Seljuk ruler Malik-Shah I conquered it and granted it to Salim ibn Malik ibn Badran, an Uqaylid commander, as compensation for surrendering Aleppo. The castle may have been built by the Numayr, but it was more likely constructed under Salim. His descendants held it almost continuously until the late 12th century, aside from a brief Crusader occupation in 1102. In 1146, Zengi besieged the castle but was murdered there by one of his own slaves. After Zengi's death, the castle passed to his son, Nur ad-Din, who carried out major construction beginning in 1168—most of what remains today dates from this period. The castle was heavily damaged during the Mongol invasions of Syria, with restoration work following in the 14th century.

Suleyman Shah, grandfather of Osman I (founder of the Ottoman Empire), is said to have drowned in the Euphrates near Qal'at Ja'bar and was buried close by. This story likely confuses Suleyman Shah with Sulayman bin Kutalmish, founder of the Seljuk Sultanate of Rûm. It is uncertain whether the actual tomb, called Mezār-i Türk, belongs to either figure. Ottoman sultan Hamid II had the tomb rebuilt. Under Article 9 of the 1921 Treaty of Ankara, the area was recognized as Turkish territory, and Turkish soldiers were permitted to guard the tomb after Syria became a French mandate and later independent.