How do you like the idea of racing 200 miles in pitch black darkness?
For most people, the idea of a good time typically involves relaxing with loved ones. We’re particularly big fans of Just Vibing (™), but sometimes it’s good to mix things up a bit and do something crazy. For most of us, that means adding an extra mile or two onto Sunday’s long run.
Of course, not everyone heeds this sense. Take ultra marathon runners, for example. You may have seen them on National Geographic. They’re an exceptionally deranged sub-species of human, and it only takes one look at the sparkle of madness in their eyes to confirm this.
You see, the ultra marathon runner culture is centered around “exercise,” a practice that involves intentionally placing strain on your body to make it stronger. Now, we should respect all cultures and learn to appreciate their differences, but we’re willing to make an exception regarding the Tunnel Ultra. You’ll see why shortly.
All jokes aside, marathon runners (and endurance athletes in general) are prone to doing insane things.
The Tunnel Ultra is a 200-mile-long fever dream of a race manufactured specifically for ultramarathon runners. Its key features are sensory deprivation and a foreboding sense of doom as runners navigate a decaying urban nightmare in the dark.
If that sounds like a good time, read on to learn about this abomination of a marathon to determine if it’s the world’s cruelest ultra-marathon.
What Is The Famed Tunnel Ultra Race?

When signing up for a 200-mile-long ultra-marathon through one of England’s oldest, dingiest railway tunnels, it’s typically a good idea to know what you’re in for.
Technically speaking, the Tunnel Ultra is pretty simple.
The track is paved with tarmac and has a slight camber. You’ll have to complete one hundred out-and-back laps within a reasonable timeframe of 55 hours.
Pitch black conditions will prevail within the tunnel between 11 pm and 5 am, while low-level lighting will be on the rest of the time. All of this really adds to the feng shui of the place, giving it that “serial killer’s lair” feeling that modern architecture so desperately tries to replicate.
There are very limited and basic facilities available. No rest shelters are available; if you want a nap, the ground is your best (and only) option. Fortunately, marathon runners are known to be able to sleep anywhere, which means they can safely rest their heads and catch a few zzzs. If you feel like snacking, there’s a checkpoint that contains coke and water, a few snack bar options, and cake.
The start isn’t directly accessible by car, so runners must carry their gear 3 miles there and back, and toilets are unavailable at the beginning. Not to worry, though; there’s a portable toilet available further on.
You are not permitted to receive any external support – no phone calls or people cheering you on. The founder has said that you are immediately out of the race if someone passes you so much as a jelly bean. It’s just as well, though, as by the time you finally emerge from the tunnel, fifty years will have passed, and your loved ones will have all moved on. Okay, not quite… but it will feel that way.
The race website describes the Tunnel Ultra as a great test of physical strength and sensory isolation. Each participant runs one mile through the tunnel and then back again on the underground road until 200 miles have been completed.
The distance must be covered in 55 hours. After 27 hours and 30 minutes, if they haven’t completed 100 miles, they are cut off. High-contrast clothing and headlamps are required since pedestrians and cyclists can also use the tunnel during the race. An individual must have completed a 100-mile race previously to enter.
Sounds a bit crazy, right?
Extreme Physical and Mental Effort Is Required
Is it possible to run a long distance from start to end in the dark? The Tunnel Ultra’s first edition was centered around this question. In keeping with Cockbain’s events, it had everything you would expect: professional runners, limited support, challenging conditions, strenuous distances, and a short time frame.
We’ve covered some of the world’s toughest ultra-marathons, but this one is truly unique.
Runners set off to do 1 mile 200 times in the Combe tunnel near Bath. Initially, it doesn’t seem hard to run through the tunnel; however, running through the tunnel 200 times can have a significant impact on runners of all skill levels.
Before each race, the runners gather to discuss what they expect to see and experience. Naturally, there’s always a general feeling of concern. The lack of natural light and the monotony of the tunnel can have a profound mental influence on everyone.
Classical music is played in the middle of the tunnel, which further adds to the sense that you may be running through a murder house. Hey, at least it’s warmer in the tunnel than outside.
To demonstrate the extreme nature of the Tunnel Ultra, here’s a quick story:
In one race that started at 3.30 pm, 34 people took off when the whistle blew. A couple of hours later, the tactics began to unfold. Taking in the herculean challenge before them, they each started taking in the environment. It was a surprise to most runners when they entered the tunnel.
It’s a 1.06-mile loop (instead of a mile loop), and it isn’t a flat gradient to run along. There’s a 1% overall gradient, which doesn’t seem that bad until you realize you must run it repeatedly. At 0.7 miles, you start a gentle decline at roughly 1.5% to the end of the tunnel. You have to run it as an incline going back.
Those numbers and percentages add up to a fun time for those who enter – they love a challenge.
An extra mileage of 13 is provided and doubles the elevation gained during the event. Fifty-five hours remains the time limit. By 5pm on day two, you can start to see a couple of runners getting away from the rest, showing the individual race strategies people have in place and their strengths.
Repetition of the same route challenges the mind in a way rarely encountered in races long or short, let alone 200-mile races. Daylight conditions the human body in many ways. When you run a regular race, you feel energized by the sunshine. Tunnels are void of reference because it’s always dark. This plays tricks on the mind too.
Who Founded the Race?
How did such an unforgiving, brutal event come to be founded? Who is the mad genius who unleashed this monstrosity into the world, and why? What did he stand to gain?
British ultrarunner Mark Cockbain – the Tunnel Ultra’s founder – wanted nothing more than to exact the pain he endured onto the rest of the world. You know, like a Batman villain. Mr. Cockbain has finished several grueling endurance events, such as the 333 km race across the Sahara desert, the Yukon Arctic race, and the Death Valley 300. So, that’s impressive.
In 1874, the Combe Down Tunnel was the longest railway tunnel in the UK without intermediate ventilation. It measures a staggering 1,829 yards (1,672 meters) long. The tunnel was shut down in 1966 and became part of the Greenway cycling track when it reopened in 2013. You instantly generate archetypal imagery and deeply rooted ideas by staging a race within a tunnel over two days.
Passing through darkness and reaching light are two of the many aspects we encounter daily: stairways, hallways, and underpasses. We experience tunnels where we enter dark, uncertain places where fear and desperation lie (we might be exaggerating a bit), and we usually try to steer clear of these states of mind.
Of course, “we” refers to normal, well-adjusted members of society. Ultra marathon runners and endurance athletes don’t count – they like running long distances in crazy conditions; the more extreme, the better!
How Many Runners Have Completed the Race?
There are about 41 contestants who participate each year, and only 13 have finished the race in the past three years. An expert in sports science points out that some studies suggest running in the dark for a long time can lead to vision problems.
It’s a miserable experience for those running, as you run for up to 55 hours without help and interaction with others. A 55-hour journey is uncomfortable in every way, no matter how you try to wrap it up.
There is a possibility that this kind of race could affect your health, particularly if you take part repeatedly. If we’re being honest, we aren’t sure why someone would do this race once, never mind repeatedly!
How Do You Enter The Tunnel Ultra?
Running ultras is not something Mark Cockbain expects runners to do to qualify for the race. You must have completed a 100-mile ultra marathon before, but this simply allows you to enter. If you want to run one of his races, contact Mr. Cockbain, and he will determine if you qualify.
Mark describes the tunnel ultra in these words: 200 miles, 100 out-and-back laps into the unknown darkness of the longest tunnel in the UK, sensory deprivation, and an endurance test like none other.
How Do You Survive the Race?
The question now is, what are your chances of surviving a race designed to destroy your mind, body, and spirit? It’s simple. Moving, eating, drinking, and going to the bathroom are the only things you need to worry about.
One competitor says it’s easier to deal with the race with the mindset that these necessities are all you need. Having a mindset like this makes the process easier to complete. Of course, as we’ve already established, marathon runners are a different breed, so take with that what you will.
Another runner said that the most important thing is 100% commitment and 100% dedication. Once doubt sets in, it’s game over. Motivating individuals takes many forms, but finishers are often motivated by the time limit, the long-lasting stamina needed, and the money spent on an event that is often unknown to those outside their immediate family and close friends.
Our Verdict on The Tunnel Ultra
How would you cope with running an ultra marathon in darkness with just a little light from your headlamp and without any social interactions or luxuries? Some have completed it, but very few compared to the number that have entered over the past three years.
Many think it’s easy, but once they are there and see the conditions for themselves, their minds play tricks on them. What drives people to do a race like this that seems like torture to the mind and body? Is it pure determination or madness? Maybe a bit of both?
If you’re in the mood for some crazy cardio in a pitch-black tunnel in one of the world’s most interesting settings, feel free to give Mark a call. As for us, we’ll sit back and watch the race from a safe distance. Good luck!