Thread by @navalhistorian

1)For those interested in matters naval & air tomorrow I'll be in #Liverpool for the reopening of one of Britain's most important #WW2 sites

2) buried deep beneath the streets of the city is the joint @RoyalNavy & @RoyalAirForce Western Approaches command bunker. #Liverpool #WW2

From here the bulk of the Battle of the Atlantic was directed-the desperate fight to keep supplies of food & war materiel flowing to Britain

4) "The only thing that ever really frightened me during the war was the U-boat peril." (#Chirchill)It was the battle for Britain's survival

5) It was also the battle that lasted from the very 1st day of the war, until the last when Germany surrendered #WW2 iwm.org.uk/collections/it…

6) Casualties were horrific. Around 1/5th of merchant sailors (from many countries) on British merchant ships & 3/4ths of German U-boat crew

7) Built underneath Derby House in #Liverpool the Western Approaches bunker was initially set up & commanded by Adm Sir Percy Noble

8) Adm Noble carried out much of thge groundwork for later success though the hard,early years & in 1942 was succeeded by Adm Sir Max Horton

9) A legendary & highly aggressive former submariner, Adm Horton took advantage of his own knowledge, Adm Noble's work, & greater resources

10) to run a highly sophisticated battle across 3 dimensions, linked heavily to the successes @bletchleypark & using the formidable talents

of both sailors & warships, such as the RN's top U-boat hunter Cpt "Johnnie" Walker of HMS Starling, & his own staff, including many WRNS

12) commanded by Supt Agnes Jean 'Nan' Currie, the tide of the Battle of the Atlantic was turned by end of 1943 (though not won until 1945)

13) Phone permitting, tomorrow I shall endeavour to tweet some pictures of this newly refurbished vital piece of Britain's #WW2 heritage

14) In the meantime please follow the @Big_Heritage team conducting the refurbishment @WestApproaches & plan a visit liverpoolwarmuseum.co.uk