Farne Islands are a series of island in Northumberland, England. Depending on the state of the tide, there are between 15 and 20 islands. They are split in two groups, the Inner Group, with its main islands Inner Farne, Knoxees Reef, East and West Wideopes, and the Outer Group, with its islands Staple Island, the Brownsman, North and South Wamses, the Longstone and Big Harcar. Staple Island is a Bird Sanctuary and can be visited between May and the end of July. Longstone Island is famous for its lighthouse, built in 1825. The group of islands is the most famous Sea Bird Sanctuary in the British Isles, and with a wide colony of Atlantic ot Grey Seals. These islands don't have a permanent population.