Hell Gill, the dramatic canyon that marks the line where the Yorkshire Dales meet the Lake District

Annunciata Elwes takes a look at Hell Gill, a trek that's not for the faint of heart.

An excursion to Hell Gill, which marks the Yorkshire Dales/Lake District border, is often compared to time spent in the belly of Jonah’s whale, a feeling enhanced by the sudden transition from exposed fellside to murky canyon when following the Hell Gill Beck downstream. Ash trees stretch to meet each other 66ft above, shutting out the light.

Not for the faint of heart (or claustrophobic), the peaty water in this 1,640ft-long limestone gash is knee, if not waist, deep and the damp, mossy walls are 3ft wide in places. One suspects only cavers are happy venturing beyond the 5ft waterfall in the middle.

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