Troller's Gill (also known as Trollerdale) is a limestone gorge which is 0.5 miles in length. It is supposedly named after trolls who used to live there (and who knows, maybe they still do).
It is also the haunt of a barguest - a demonic hound that local folklore claimed the life of a young man in the 19th century.
Pictured left is Trollers Gill courtesy of James F. Carter.
For further information, please read Haunted Britain and Ireland by Richard Jones.