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Runners and times in full
Around 550 intrepid walkers from across the UK and beyond set off from Aireville School in Skipton to take on the gruelling 100km Trailtrekker walk in aid of Oxfam.
The 62-mile circuit through some of the Dales' most picturesque scenery will take the participants up to 30 hours to complete, with most expected to reach the finish line back in Skipton sometime tomorrow morning. Competitors walk in teams of four to provide one another with support and encouragement.
"We're aiming to do it in under 24 hours," said Andy Geldard, a Skipton-born member of the Critical Path Hikers team. "I've done quite a lot of training over the past couple of months around the Dales. We're really looking forward to it now."
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As the warm summer sunshine began to break through the early morning mist, walkers gathering at the start line were advised to keep topped up with fluids and suncream throughout the day. Temperatures are expected to soar as high as 25C in some parts, and there was also some trepidation about forecasters' warnings of possible showers later in the day.
But spirits remained high as teams tucked into a breakfast of porridge and bacon butties laid on by the army of volunteers helping out at the event, before the first wave of trekkers swept off armed with backpacks, sun hats and walking poles at 7am.
Oxfam hopes their sponsorship efforts will raise hundreds of thousands of pounds for its aid projects around the world.
"It's gone really well so far," said Oxfam's James Terry. "I'm delighted. The weather has been beautiful for the start, though it is going to get hot and humid.
"I take my hat off to everyone taking part - it's a fantastic effort and makes a fantastic contribution to Oxfam. It really makes a difference to what we do."
Trailtrekker is one of several 100km sponsored walks organised by Oxfam around the world each year. But few, if any, can match the arduous nature of the Yorkshire route, which takes in some of the Dales' toughest peaks, including Pen-y-ghent. The 100km treks were originally based on a challenging training exercise for the Gurkhas but have grown into some of Oxfam's biggest worldwide fundraisers.
"We did it last year, and we're a bit of a veteran team when it comes to these events," said Catherine Slater, part of the Three Aussies and a Yank team which has members from Melbourne, Sydney and Vermont.
"We've done others around the world - but this one is the hilliest! That makes it a little bit harder. But we love the spectacular scenery, the friendly friendly people - and going over Pen-y-ghent!"