One of the towers of Qalʿat (castle) Shayzar

One of the towers of Qalʿat (castle) Shayzar

Exterior view of Krak des chevaliers (Qalʿat al-Husn)

Exterior view of Krak des chevaliers (Qalʿat al-Husn)

Krak des chevaliers (Qalʿat al-Husn), Gothic vaults

Krak des chevaliers (Qalʿat al-Husn), Gothic vaults

Euphrates valley south of Qalʿat Najm as it looked before the flooding of lake Tishrin

Euphrates valley south of Qalʿat Najm as it looked before the flooding of lake Tishrin

Jurn Kabir, a typical old house of the Euphrates valley near Qalʿat Najm with a large log (willow) transverse to the longitudinal axis.

Jurn Kabir, a typical old house of the Euphrates valley near Qalʿat Najm with a large log (willow) transverse to the longitudinal axis.

The northern entrance of the historical city of Dura Europos (Qalʿat as-Salihiyya), end of 4th century BC

The northern entrance of the historical city of Dura Europos (Qalʿat as-Salihiyya), end of 4th century BC

Palmyra, Colonnaded axis and Qalʿat Ibn Mʿan in the back

Palmyra, Colonnaded axis and Qalʿat Ibn Mʿan in the back

The northern entrance of the historical city of Dura Europos (Qalʿat as-Salihiyya), end of 4th century BC

The northern entrance of the historical city of Dura Europos (Qalʿat as-Salihiyya), end of 4th century BC

View on the Euphrates River from the site of Dura Europos (Qalʿat as-Salihiyya)

View on the Euphrates River from the site of Dura Europos (Qalʿat as-Salihiyya)

The gate of south-western side, Dura Europos (Qalʿat as-Salihiyya)

The gate of south-western side, Dura Europos (Qalʿat as-Salihiyya)

A side from archaeological city of Dura Europos (Qalʿat as-Salihiyya)

A side from archaeological city of Dura Europos (Qalʿat as-Salihiyya)

The northern entrance of the historical city of Dura Europos (Qalʿat as-Salihiyya), end of 4th century BC

The northern entrance of the historical city of Dura Europos (Qalʿat as-Salihiyya), end of 4th century BC

The northern entrance of the historical city of Dura Europos (Qalʿat as-Salihiyya), end of 4th century BC

The northern entrance of the historical city of Dura Europos (Qalʿat as-Salihiyya), end of 4th century BC

Dura Europos (Qalʿat as-Salihiyya), Roman amphitheater

Dura Europos (Qalʿat as-Salihiyya), Roman amphitheater

The northern entrance of the historical city of Dura Europos (Qalʿat as-Salihiyya), end of 4th century BC

The northern entrance of the historical city of Dura Europos (Qalʿat as-Salihiyya), end of 4th century BC

Excavation works, Dura Europos (Qalʿat as-Salihiyya)

Excavation works, Dura Europos (Qalʿat as-Salihiyya)

The northern entrance of the historical city of Dura Europos (Qalʿat as-Salihiyya), end of 4th century BC

The northern entrance of the historical city of Dura Europos (Qalʿat as-Salihiyya), end of 4th century BC

Excavation works, Dura Europos (Qalʿat as-Salihiyya)

Excavation works, Dura Europos (Qalʿat as-Salihiyya)

The northern entrance of the historical city of Dura Europos (Qalʿat as-Salihiyya), end of 4th century BC

The northern entrance of the historical city of Dura Europos (Qalʿat as-Salihiyya), end of 4th century BC

The northern entrance of the historical city of Dura Europos (Qalʿat as-Salihiyya), end of 4th century BC

The northern entrance of the historical city of Dura Europos (Qalʿat as-Salihiyya), end of 4th century BC

The northern entrance of the historical city of Dura Europos (Qalʿat as-Salihiyya), end of 4th century BC

The northern entrance of the historical city of Dura Europos (Qalʿat as-Salihiyya), end of 4th century BC

The northern entrance of the historical city of Dura Europos (Qalʿat as-Salihiyya), end of 4th century BC

The northern entrance of the historical city of Dura Europos (Qalʿat as-Salihiyya), end of 4th century BC

Damascus citadel from the inside, round 1930

Damascus citadel from the inside, round 1930

Southwest side of the Byzantine Basilica, Qalʿat Burqush

Southwest side of the Byzantine Basilica, Qalʿat Burqush

The Byzantine basilica, view from the south, Qalʿat Burqush

The Byzantine basilica, view from the south, Qalʿat Burqush

Capital in the Byzantine Cathedral, Qalʿat Burqush

Capital in the Byzantine Cathedral, Qalʿat Burqush

Remains of a façade of the Roman temple, Qalʿat Burqush

Remains of a façade of the Roman temple, Qalʿat Burqush

Ruins of Qalʿat ash-Shugr wa-Bakas on the edge of a mountain slope

Ruins of Qalʿat ash-Shugr wa-Bakas on the edge of a mountain slope

Parts of Qalʿat Shayzar with one of the towers

Parts of Qalʿat Shayzar with one of the towers

Remains of the Byzantine Cathedral, Qalʿat Burqush

Remains of the Byzantine Cathedral, Qalʿat Burqush