The region of Semna is 15 miles south of Wadi Halfa and is situated where rocks cross the Nile narrowing its flow—the Semna Cataract. Semna was a fortified area established in the reign of Senusret I (1965–1920 BC) on the west bank of the Nile at the southern end of a series of Middle Kingdom fortresses founded during the Twelfth Dynasty of Egypt (1985–1795 BC) in the Second-Cataract area of Lower Nubia. There are three forts at Semna: Semna West (Semna Gharb), Semna East (Semna Sherq, also called Kummeh or Kumma), and Semna South (Semna Gubli). The forts to the east and west of the Semna Cataract are Semna East and West, respectively; Semna South is approximately one kilometer south of Semna West on the west bank of the Nile.