External relations of Guernsey both islands retain their independence with regards to domestic affairs but internationally, the islands would be regarded as one state. A Guernsey-Jersey double taxation agreement was first signed in 1956. In 1998 Guernsey and Jersey electricity companies formed the Channel Islands Electricity Grid to operate and manage the submarine cables between Europe and the Channel Islands. Guernsey has formed part of the British–Irish Council since it was formed in 1999, as does Jersey. Meetings take place twice a year, in 2004, 2010 and 2014 the meetings have taken place in Guernsey. Its stated aim is to "promote the harmonious and
German fortification of Guernsey Guernsey comprising: Commanding Officer of the German garrison, Lieutenant-General Graf von Schmettow, nephew of Gerd von Rundstedt commander of OB West (Commander-in-Chief West), ordered the writing of a 500-page book that described the fortifications in great detail, illustrated with maps, photographs and coloured drawings. A copy was destined for Hitler. The chapters from the original book have been reproduced in a set of ten paperbacks. "Festung Guernsey" (fortress Guernsey). Whether the Islands were impregnable was never tested, except for "Battery Bluecher" in Alderney. Alderney was considered too well-protected against aircraft attack so HMS Rodney was tasked with shelling it. "Rodney"