RAF Waddington was opened in 1916, during the First World War, operated throughout the Second World War, and is still open at present (2013). {1}{2}{3}{4} There are possibly surviving pillboxes within RAF Waddington according to a member of the public who worked on site. These may be examples of the modern Yarnold Sangar, rather than a Picket Hamilton pillbox. Yarnold Sangars were used at Waddington and are very similar in appearance to a raised Picket Hamilton pillbox, but are made of interlocking concrete tubes, the lower of which has a arched entrance and rests directly upon the ground. Sometimes this entrance is simply protected by sandbags, but at some sites a curved semi-circular concrete panel blast wall is also used. It is also possible to find tall sangars that have used more concrete tubes to gain height over an obstacle that blocks the fields of view or fire. {5}