A new sand castle and an old lighthouse.  
Robert Louis Stevenson often played on Yellowcraig beach opposite Fidra but his sand ‘castles towers’ would have been of a slightly different shape.  The lighthouse was built by his father and uncle with the Stevenson family being responsible for building most of the lighthouses in Scotland.     Fidra light was first lit in 1885 and RLS was inspired by the islands to which he had been taken and he based his map of ‘Treasure Island’ on the shape of Fidra.   In 1870 the lighthouse became the first Northern Lighthouse Board light to be converted to unattended automatic installation with power supplied from the mainland through a submarine cable. A very similar light from a neighbouring lighthouse is now in the museum in Edinburgh.
Thanks to Bobblips for today’s challenge of ‘old’.