My wife Jane and I have a "peedie" farm overlooking the large natural anchorage of Scapa Flow. A major naval base during both world wars, it's now the home of the oil industry in Orkney. The causeway you can see is one of four built during World War Two, to block permanently the Eastern channels into Scapa Flow. This was done on the orders of Winston Churchill, after the sinking of HMS Royal Oak in Scapa Flow on the 14th October 1939, by a German submarine U47.