Taveuni is located at the northern end of the Koro Sea, and is entirely the product of volcanic activity. Fiji's third largest island is separated from Vanua Levu by the Somosomo Strait. The island is between wide and long, is the top of a dormant, elongated shield volcano which erupted from a northeast-southwest trending rift on the ocean floor. About 150 volcanic cones dot the island, including Uluigalau, Fiji's second highest peak at , and Des Vœux Peak, next in height at . There have been at least 58 volcanic eruptions since the first human settlement around 950-750 BC, all of which affected the southern two-thirds of the island. Major eruptions from 300–500 AD caused abandonment of the southern areas until about 1100 AD. The latest eruption produced a lava flow at the southern tip of the island around 1550. The island's central ridge delineates the greatest volcanic activity surrounding volcanic vents.