The Royal Flying Corps hangars at Camp Borden are the oldest examples of this type of construction in existence in Canada. These hangars, which are an essential element of the first Canadian military aerodrome, were erected as temporary facilities in 1917, and housed various air training schools. They witnessed the birth of Canada's national air force, the Canadian Air Force in 1920, which became the Royal Canadian Air Force in 1924. (taken from National Historic Site plaque at the museum)
While most of the hangars have been restored and have found new life as working buildings for the base, and one which acts as a museum, at least three of the hangars sit completely empty and unused, in a very sad state. One of the abandoned hangars appears to have the roof close to caving in. The public may visit this site, although it is located on an operational military base, expect tight security. The air museum lies between the abandoned hangars.
I suggest visiting on weekends when the museum is open. So much to see and photograph, and a great piece of history that may not be with us much longer.