During World War II, there was a U.S. Navy base on the north side of Morro Rock where sailors were trained to operate LCVPs. The breakwater on the southwest side of the Rock was built in 1944-45 to protect the LCVPs entering and leaving the harbor. Soldiers from Camp San Luis Obispo would come to Morro Bay and practice loading into the LCVPs. Many of those men were at Normandy on D-Day.