Dayr az Zawr, city in eastern Syria, capital of Dayr az Zawr Governorate, on the Euphrates River. A bridge crosses the river here. Situated near the site of an ancient city, Dayr az Zawr houses an archaeological museum, founded in 1974. The city was an administrative center under the Turks in the 19th century, when it was made capital of the Zor region. The name is also spelled Dayr az Zur, Dayr az Zor, and Deir ez-Zor. Population (1992 estimate) 125,000.