In 1942 the Naval College in Dartmouth was bombed, staff evacuated and the damaged building was left empty. The Philip Boatyard nearby was also hit .The college reopened temporarily when the area became a centre for Combined Operations, the American troops using the surroundings as an important base while their ships prepared for the Normandy landings.

At the outbreak of war the paddle steamer services stopped. Both Kingswear and Totnes were moored at Kingswear and Dartmouth Castle was laid up at Old Mill Creek. Dittisham Castle was sold in 1940 to a local coal merchants.

In 1941a limited passenger service started again using Totnes Castle and towards the end of the war saw Kingswear Castle being chartered by the U.S. Navy as a tender and a liberty ship. For some time she also became a naval stores moored to Dittisham pier.

Compton Castle was also kept busy . Perhaps she had a little more of a warlike appearance. Maybe she'd even changed to a grey colour. Doubtless she carried on pottering about on the river like she always did, except for her cargo. The Navy were using her as an ammunition carrier.

The Royal Naval College reopened in 1946.

Dartmouth Castle never left Old Mill Creek. Her remains lie there still.