The wind brings tears to the eyes as I make my cautious way to the brink of Hell Gill, the limestone chasm that once marked the boundary between Yorkshire and old Westmorland. Below, the infant river Eden, at this point called Hell Gill Beck, races north en route for Carlisle and the Solway Firth.
It was here, according to legend, that the 18th-century highwayman Dick Turpin eluded his pursuers by spurring his horse, Black Bess, into a flying leap across the 5ft gap.
Today, there is a bridge, carpeted with daisy speckled turf, but you can see white water churning below. All around are verdant fields with white limestone scars topped by black millstone grit. This is Pennines watershed country, where rain falling one side of upper Mallerstang flows down to the Eden and the Irish Sea; and on the other into the Ure. Destination? The North Sea.
I look down at my Ordnance Survey map, on which Ben Lyon, chair of the Upper Eden Rotary Club’s Yomp committee, has marked the highlights of the Yomp Mountain Challenge, a charity event commemorating the British forces’ march across the Falklands to retake Port Stanley in 1982 from Argentina.
The 23-mile skyline trail leaves the market town of Kirkby Stephen to traverse Wild Boar Fell, where, on this day, I see wind-tattered smoke dispersing from a steam-hauled train on its lower slopes.
Then it’s up Swarth Fell, dipping back into Mallerstang, across Hell Gill Beck and along the opposite high ridge, over Mallerstang Edge and then back to town via Nine Standards Rigg.
Lyon has been tramping these fells for years. If it’s solitude you want, this is the valley to be, he says. Except on the day of the yomp, this year on Sunday 5 June. Last year 200 walkers and fell runners attacked the full circuit with its 1,300-metre climb; 180 attempted the less challenging half round; and another 100 or so finished the six-mile kiddies-and-parents walk.
“Press on, regardless” is Lyon’s motto. Even at the age of 76? “Absolutely. I completed the yomp last year, no problem.”
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