 In the First World War , Devonport was the headquarters of Western Approaches Command until 1941 and Sunderland flying boats were operated by the Royal Australian Air Force . It was an important embarkation point for US troops for D @-@ Day . The city was heavily bombed by the Luftwaffe , in a series of 59 raids known as the Plymouth Blitz . Although the dockyards were the principal targets , much of the city centre and over 3 @,@ 700 houses were completely destroyed and more than 1 @,@ 000 civilians lost their lives . This was largely due to Plymouth 's status as a major port . Charles Church was hit by incendiary bombs and partially destroyed in 1941 during the Blitz , but has not been demolished , as it is now an official permanent monument to the bombing of Plymouth during World War II . 
