Royal Marines from 11 Amphibious Trials and Training Squadron, based at RM Instow, showed how the amphibious craft have advanced since landing on the Normandy beaches on June 6, 1944. D-Day veteran Clifford Coates and the private owners of World War Two vehicles were among those invited to Instow to meet the squadron and see the facility. The North Devon base, an out station of 1 Assault Group Royal Marines (1AGRM), was built in late 1942 as a training and testing facility for troops preparing for the invasion of Nazi-occupied Europe. Around 10,000 American GIs were stationed in North Devon during World War Two for training in the run up to D-Day, which included Instow. A programme of events under the Devon D-Day umbrella is currently running at museums and locations across the area. Today, the base at Instow is responsible for developing new equipment to meet the needs of the Royal Marines. In a two-mile radius of Instow, there is easy access to sheltered and open water but also five of the seven beach types found on the planet - making it an excellent place to test and develop equipment. Colonel Chris Haw, commanding officer of 1AGRM, said after the commemorative event: "This base was used during World War Two to waterproof and trial tanks and vehicles that would go on to Normandy. "It was a centre for innovation then and it continues that today. We trial all the new equipment coming in and we teach people how to waterproof vehicles. "Today was about showing what we do now at Instow but also remember the courage and determination shown by all our predecessors." As part of the day, a Willy's MB jeep from D-Day and one used by current marines were driven through the base's dip tank - a ramp leading down to one-and-a-half metres of water to simulate leaving a landing craft. Mr Coates, from Bideford, served in the Royal Marines during D-Day as a coxswain on one of the landing crafts. The 95-year-old said: "The build up to D-Day was all about training, training, training. We trained so much that running on the beaches was like running on a normal road. "When we set off there were thousands of landing craft. I had never seen so many vessels in my life." Speaking about the base at Instow, Mr Coates added: "The training at Instow was very important. How successful we were depended on the training here, it was most essential for us."