On the left bank of Mid Euphrates (across Zalebiye) 66 km north of Deir Ezzor (100 km south of Raqqa); Halebiye was one of the most formidable Byzantine fortifications in Syria, the culmination of Justinian's ambitious policy of securing the frontier of the Later Roman Empire on the Euphrates. The site is particularly splendid at sunset when the shadows fall across the stark hills and the sun strikes a warmer luminescence in the stone.

Though what you now see is basically Byzantine construction of the sixth century, Halebiye was first fortified during the apogee of Palmyrian control in the area, in the mid third century. When the Romans responded to Zenobia's rebellion by occupying the Palmyrene domains in 273, they took Halebiye (named after a Palmyrian Queen).

The great consolidation of the site dates to the reign of the Byzantine Emperor Justinian (ruled 527 - 65). In Syria, he put considerable store by retaining control of a region which had become an important center of Christianity and securing it against the Persian threat. Halebiye along with the earlier fortifications of the pilgrimage city of Resafe were the most conspicuous results of his policy.

The Arabs used the great fortification from time to time but it was later largely left to decay. The fortifications originally contained a small garrison city with the usual range of amenities within the 12 ha walled area. Also the citadel speaks of how many occupiers re-fortified it. And last but not least, the funerary towers and rock-cut tombs of the late Roman period can be watched along the river to the north of the city.

Zalebiye:

On the right bank of Mid Euphrates (across Halebiye) 66 km north of Deir Ezzor (100 km south of Raqqa); the history of Zalebiye marches closely with that of the complementary fortress on the Euphrates, Halebiye. Being in a worse state of preservation, smaller in extent, and until recently less accessible, Zalebiye has been infrequently visited.

The fortress, like Halebiye, was established in the period when the Palmyrene were unwisely attempting to assert their control in the area to test Roman dominance. It was improved as part of the defensive works of the Byzantine Emperor Justinian. It was more damaged than Halebiye due to the use of less solid construction techniques and earthquakes and river flooding effects.

These works probably date back at least to the first century AD and probably to the late Bronze Age. The canal was still in use in the Arab middle ages when it was named after Semiramis, the legendary Arab queen.