Mount Gower is the highest mountain on Lord Howe Island. With a height of 875 metres (2,871 ft) above sea level, and a relatively flat 27-hectare (67-acre) summit plateau, it stands at the southern end of Lord Howe, just south of the island's second highest peak, the 777-metre (2,549 ft) high Mount Lidgbird, from which it is separated by the saddle at the head of Erskine Valley. Lagoon Beach is a semi-enclosed, sheltered coral reef lagoon located on the western coast of Lord Howe Island. Norfolk Island Pines, endemic to Norfolk Island, 900km to the north-east of Lord Howe Island, have become established in parts of Lord Howe Island.