town and Mediterranean port, northern Algeria, on the Gulf of Arzew. Known as Murustuge in the 11th century, it contains Bordj el-Mehal (the old citadel), attributed to the 11th-century Almoravid emir Yusuf ibn Tashufin. Captured in 1516 by the sea rover Khayr ad-Din (Barbarossa), the town passed to his brother, enjoyed great commercial prosperity, and then declined. It was garrisoned by the French in 1833.
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