Tobruk (tōbrŏŏk´), Arab. Tubruq, city (1984 pop. 75,282), NE Libya, a port on the Mediterranean Sea. It was a fiercely contested objective in World War II (see North Africa, campaigns in). Tobruk was first taken by the British on Jan. 22, 1941. When the Germans under Erwin Rommel drove the British out of Libya (Mar.–Apr., 1941), the Australian garrison at Tobruk was isolated. However, the Australians were provisioned by sea and withstood repeated German attacks. British Field Marshal Claude Auchinleck's drive late in 1941 relieved the siege (Dec. 10). During Rommel's second offensive (begun May 26, 1942), Tobruk fell (June 21) after a one-day assault. The city was retaken by the British on Nov. 30, 1942. The port facilities were expanded in the 1960s to link the city to nearby oil fields.