Challenge description

The Tunnel is a mind bending test of extreme endurance and sensory deprivation. This challenge is a 200 mile ultramarathon through the darkness of the UK'S longest foot tunnel. You will run on flat terrain but in the pitch black between 11pm and 5am, there will be low level lighting in effect at other times.


The Combe Down tunnel is in Bath, Somerset and there will be a checkckpoint at the south end of the tunnel. You will have 55 hours to run approximately 100 'out-n-backs', or 200 times through the tunnel, which is possibly the greatest mileage ultramarathon ever run 99% underground.


31st March -2nd April 2023




Enter The Tunnel


Entrants are limited. All applicants MUST have a minimum of a 100 miler as a qualifier. This is a very low key, no nonsense extreme test of running ability and endurance - please only apply and make payment if you meet the required pre-requiste of 1 x 100mile Ultramarathon.


No refunds, transfers, or deferrals.


Questions? Contact us

Thanks for submitting!


Registration information

This challenge will take place in Bath, Somerset through the Combe Down tunnel. Registration is as the Check Point on the south end.


What's included

  • This is a very, very basic and limited challenge with no shelter/rest area.

  • Checkpoint has water/coke only and snacks (bars, cake, gels etc). Bring your own drinking mug/container.

  • Drop box area.

  • Portaloo. 

  • No parking directly at start.

  • No toilets at start.



  • No refunds, no deferrals.

  • You must not come if you feel unwell/have any Covid symptoms.

  • You must bring your own cup/drinking bottle.

  • We will only be providing water and basic individually wrapped snack type food.

  • Anything you bring you MUST take away with you (kit, boxes etc).

  • No headphones, no sticks, no outside support.

  • The tunnel is open to the public and is especially used by bikers, so LHS running only and tunnel rules must be obeyed.

  • No littering.

  • Hi Vis must be worn at all times.

  • Headtorch worn in dark hours.

  • Whistle and phone must be carried.

  • One small waterproof box/bag can be left at own risk in baggage area.

  • THIS IS NOT A SEE HOW FAR YOU CAN GET IN 55 HOURS EVENT (you will be timed out if not at 100 miles in 27:30).


2023 Runners

Watch this space!


Race results

View race results for The Tunnel, 2021