Israeli naval forces were used to conduct amphibious operations to achieve tactical surprise and to isolate Tyre and Sidon at the outset of the campaign. These were technically difficult to conduct due to a shortage of landing craft. Indeed, the Israel Navy had to keep shuttling the landing craft back and forth the 55 kilometers between the beaches north of Sidon and Israel. At Sidon, the Navy also took the ancient port under fire. Due to Beirut's coastal location, the Israeli Navy also played an important part in isolating the PLO and other hostile forces in West Beirut near the coast. Additionally, the Navy provided modest fire support using its 76mm guns, but its main activities involved coastal patrols to prevent reinforcement of PLO positions or the seaborne delivery of supplies. Other tactical missions included preventing opposition forces from mining the beach or preparing defensive position.