The Bozdoğan Kemeri (Valens Aqueduct) is located in the Fatih quarter of Istanbul, in the valley between the hills where Istanbul University and Fatih Mosque stand today. Ataturk Boulevard runs underneath its arches. The aqueduct was built during the reign of Emperor Valens ca. 375 CE, and later repaired and expanded under Roman, Byzantine, and Ottoman rulers.
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surviving section approx. 921 m long