The castle (Qalat Shmamis) was first built, on top of an extinct volcano, in the 1st century BC by Sampsiceramus I, the first Priest King of the Royal family of Emesa.

It was rebuilt by Assad ud-Din Shirkoh, an Ayyubid governor of Homs; the date of this reconstruction was set by Abu Fida in 626 AH (AD 1228), while Muhammad Kurd Ali in his book "al-Sham Plans" fixed it at 627 AH (AD 1229).

This castle was built on a basaltic layer covering a conical top of the mountain.

This summit is surrounded by a moat 15 m depth, and provides a very deep well to meet the water needs for the castle, and another well for supplies.

The importance of this castle is due to its location which allows to observe a circular area of more than 50 km in diameter.