In addition to providing day-to-day recreational enjoyment, University Parks has always proved a popular site for the public to commemorate special occasions. Children from the City's elementary schools enjoyed a tea party on 22 June 1898 in celebration of Queen Victoria's Diamond Jubilee (1897).
Schoolchildren were again entertained in the Parks on Coronation Day in 1911 and to commemorate Peace on 19 July 1919 (unfortunately the planned games were cancelled due to heavy rain that day). Public events were also held to mark the Silver Jubilee of King George V and to celebrate the coronations of both King George VI and Queen Elizabeth II.
During the First World War, the Parks were used for drilling and training exercises. Aeroplane hangars were erected and soldiers were billeted in a camp in the south eastern corner. An allotment area for growing vegetables was provided near Lady Margaret Hall. All University sports ceased apart from tennis and croquet and the number of staff employed to maintain the Parks was reduced to a minimum.
Between the wars, bands played in the Parks on summer evenings. In 1927, the Curators reported that the attendance at these averaged 8,000. The following year a total attendance of 70,000 was recorded at five concerts given by the City Military Band. As early as the beginning of the 20th century, the large numbers of the public using the Parks on summer evenings and weekends caused the Curators to request the services of a police constable from the City Council's Watch Committee.
During the Second World War the area was ‘Dug for Victory’ again to provide around eighty vegetable allotments. The quantity of food produced in the various plots was probably variable because of the poor quality of the soil over much of the area. Aerial photographs show the allotments located to the south of the path to High Bridge, between Thorn Walk and Oak Walk, with some to the north of the Science area.
The war years also saw the construction of an air raid shelter under the Cricket Pavilion and obstructions were placed in the open spaces to prevent aircraft landing. At the end of the war measures were put in hand to reinstate much of the area, but the iron railings along the south and west boundaries, which had been removed to make munitions, were not replaced until the late 1960s.