The first incarnation of Ais Gill signal box opened on 2nd August 1875 (when the full length of the Settle & Carlisle Railway officially opened for goods traffic).
A replacement box probably opened at some point between 1890 and 1906 (although the exact date is subject to some debate[1]).
The signal box at Ais Gill was last operated on a regular basis on 28th July 1978 (although it was re-opened briefly for a "special" reason on 17th December 1978) and it was officially closed on 28th January 1982.
It was subsequently purchased by the Midland Railway Trust Ltd. and relocated to the Midland Railway Centre at Butterley, in Derbyshire.
[1] Each of the following (generally reliable) reference sources cites a different date for the opening of the replacement signal box at Ais Gill:
► 26th April 1890, in the caption for plate 101 of Anderson, V.R. & Fox, G.K.: "Stations & structures of the Settle & Carlisle Railway" (Oxford Publishing Company, 1986).
► 24.6.1900, on page 184 of Gough, John: "The Midland Railway - A Chronology" (The Railway and Canal Historical Society, 2nd edition,1989).
► 1906, in Historic England's official List Entry Number 1335401 (which covers the structure in its current location at Butterley).
