The outlying islands of Scotland are not part of the larger archipelagos and island groups of Scotland—the Hebrides, the Northern Isles or the Islands of the Forth and Clyde estuaries. None of these islands are currently inhabited and few of them ever were, although Hirta was occupied from the Neolithic age until 1930 and Stroma was permanently occupied until the 1970s and thereafter by lighthouse keepers and their families until 1996. Several other outlying islands have lighthouses, none of which is still staffed.