In 1957, the Royal Air Force and then the Army landed on Hirta and started to build a camp to watch and track missiles fired from a base on the Outer Hebrides. Today the buildings and radar station are still there but are no longer run by the Army. The people who work there now still watch for missiles. They also support the National Trust for Scotland (NTS) by providing phones, electricity & water. They also look after the islands during the winter when there are no NTS staff living there.