RAF Coningsby in Lincolnshire will celebrate the 100th anniversary of one of its squadrons today.
To mark it, 29 Squadron will take part in a special parade - watched by Prince William - who is the Honorary Air Commandant of Royal Air Force Coningsby.
The air base is also home to the Battle of Britain Memorial Flight, which will perform a flypast.
The RAF base is responsible for the delivery of Quick Reaction Alert (South), meaning it can launch armed aircraft at short notice to investigate potential threats to UK airspace.
The 29(R) Squadron instructs both new pilots and pilots experienced on other platforms how to operate the Typhoon aircraft.