Smith's Lawn area of the Park began to be used for flying in the 1920s, an activity which continued in various forms until the early 1950s. Improvements were made to the grass landing area in the mid 1930s, when it was used by the Prince of Wales (later Edward VIII). He operated several different types of aircraft from here, including several types of de Havilland airplanes, ranging from Moths to Dragon Rapides. On 29 April 1931, Gordon Olley landed a large (for the time) twin-engine Imperial Airways airliner, the Armstrong Whitworth Argosy ("City of Glasgow"), at Smith's Lawn. In 2016, the Duke of Edinburgh unveiled a memorial at Smith's Lawn to its use as an airfield. He himself had made his first solo flight from there in 1952, after regular use of the site as an airfield had ceased. Second World War During the war, aviation related activities included a factory dispersal site (to minimize the risk of Luftwaffe bombing) for Vickers-Armstrongs, who built and maintained Wellington bombers here. Other wartime aviation activities included use as a Relief Landing Ground for de Havilland Tiger Moth trainers at nearby No. 18 Elementary Flying Training School at Fairoaks. The Smith's Lawn area of the Park was also used for housing troops. During the 1940s, much of the deer park was ploughed and farmed for food, which involved the felling of hundreds of ancient trees. Over 200 large bombs fell on the land, including several V-2 rockets. During the 1948 Summer Olympics, the park was used as the road cycling venue. In the 1950s, the Park was gradually turned into the recreation area open to the public that it is today. This involved the re-planting of Savill Gardens (which had been allowed to run wild during the war) and the new Valley Gardens. In 1951, a large wall for creeping plants was built at Savill using bricks from bombed-out London buildings. In 1958, a Totem pole was installed nearby, a gift from British Columbia to the Queen. Protests In 1972 the Irish anarchist Ubi Dwyer organised the "People's Free Festival", the first of the Windsor Free Festivals in the Park, attended by 700 people. A co-organiser Sid Rawle claimed that Windsor Great Park has been common land until the 18th century, and illegally inclosed (made private) by George III. Prince Philip, Duke of Edinburgh was reported to be "furious". Ubi and his allies