Mark Cockbain is the founder and Race Director of Cockbain Events. He has completed more than 300 marathons and ultramarathons, including some of the toughest races in the world. Mark has run John o' Groats to Lands End (JOGLE) in 15 days, 3 hours, 40 minutes and cycled the same 980-mile route in nine days – the first person to officially run and cycle JOGLE.

His long-distance interest was sparked when he ran his first marathon in Paris in 1997 and he has since completed the OUTLAW Ironman Triathlon in 16:32:45. These days, Mark's boundless energy and enthusiasm are directed towards promoting many of Britain's most severe ultra challenges with The Tunnel 200 miler possibly being the maddest race of all.

The Tunnel takes place through the darkness of the UK's longest foot tunnel – Combe Down Tunnel, near Bath city centre – comprising 100 out and back 'laps' of a mile in each direction, with a strict 55-hour time limit. The Tunnel is a mind-bending test of extreme endurance and sensory deprivation as runners compete on flat terrain but in the pitch black between 11pm and 5am with low-level lighting in effect at other times.

This makes The Tunnel possibly the greatest mileage ultramarathon to ever be run almost entirely underground with competitors only emerging into the light briefly to visit the south end checkpoint before turning to plunge back into the tunnel for another lap – with 99 tempting opportunities to drop out!

As competitor Mike Raffan explains: "You run from one end to the other, turn around a traffic cone, come back again, and just keep going". Mike was seventh last year (52:49) in a race won by Guy Bettison (43:06).

The race is so mind-numbingly tough that only two finished the inaugural event in 2019. Another 14 managed the 2021 edition, including the first-ever woman to survive the challenge. Mandy Foyster (54:55) had just five minutes to spare when she completed her 100th 'lap' and 200th mile.

This year's The Tunnel takes place from 31 March – 2 April 2023 and costs £250 to enter. Competitors must have completed an ultramarathon of at least 100 miles to be qualified for Britain's maddest, most underground ultrarunning challenge.

Race details at The Tunnel website here.

Event information and previous race results at runABC South race listing here.

Image courtesy Chia Charge for Cockbain Events on Facebook