Flat Holm Island, near Penarth, Vale of Glamorgan.

Flat Holm is an island 4 miles out from Lavernock Point in the Bristol Channel. It has been inhabited in one form or another since the Bronze Age. In the 18th century it became a base for smugglers as it has a series of concealed natural tunnels, the main contraband being tea and brandy. Flat Holm was fortified in 1860 with big guns to protect both Bristol and Cardiff from a possible invasion by the French. A stone barracks was built to sleep 50 soldiers, and in WW2 around 350 troops of the Royal Artillery were stationed there operating heavy guns, and a radar station. Around 1896, an isolation hospital was built to house many patients who were suffering from Cholera, and the last person to die there was suffering from Bubonic Plague. The hospital closed in 1935 and is now derelict. In 1897, 22 year old Guglielmo Marconi transmitted the first wireless radio signals from Flat Holm to Lavernock Point.  There have been many shipwrecks on the island over the years and a lot of those who died as a result are buried there, so bad was the number of shipwrecks, that in 1736 a Mr William Crispe paid £800 of his own money to build a 98 foot high lighthouse there which came into service in 1738. The island is now a Site of Special Scientific Interest and is home to many rare species of plants, birds and slow worms