Troller's Gill is a limestone gorge, close to the village of Appletreewick in the Yorkshire Dales (grid reference SE068619). Legend has it that the Gill is the home of trolls, and the mythical monstrous black dog Barghest. It is also the setting for Roger and the Rottentrolls, which draws upon these legends. It is also the location of an old lead and later fluorspar mine which was last worked in the 1960s.