Herm is only  miles long (north-south) and less than half a mile wide (east-west). In the northern part of the island are two hills, Le Petit Monceau and Le Grand Monceau. To the north of these is a common, leading to Mouisonniere Beach on the northern coast, with Oyster Point in the northwestern corner and La Pointe du Gentilhomme or Alderney Point at the northeastern corner. To the east of the common is Shell Beach and to the west is The Bear's Beach, leading down to the harbour. Half of the coastline of the northern part of the island is surrounded by sandy beaches; the southern half is rocky. Much of Herm's bedrock is granite. In 2008, Adrian Heyworth, who was at the time the island's tenant, said that two or three metres of sand were being lost annually at Alderney Point.