for those who love the outdoors

27 September, 2023


Hard lessons learnt from running the Eiger Ultra Trail

Have you ever bitten off more than you can chew but knew there was no going back? If you are a runner then you may be more than familiar with this feeling of dread mixed with inevitability that can hit you even when you are doing something you actually enjoy.

Trail 1

You might feel this way when a little bad weather is dialled up to biblical while you are still mid-run. Or maybe you face this whenever you step up to a new starting line for the first time. Even runners who appear fearless will experience this same feeling when they attempt to do something that is just a little outside their comfort zone. Fortunately, one of the universal truths of running also happens to be the well-known saying, that ‘what doesn’t kill you makes you stronger’. In other words, having the resilience to overcome whatever challenge is in front of you can be immensely rewarding.

With this in mind, I recently returned from a running holiday in Switzerland where my husband and I continued to train for an upcoming autumn marathon. Unlike our previous running holidays where we ran from destination to destination over a week, this time we based ourselves in one location – Grindelwald – where we planned to run out from each day. Since Grindelwald hosts the annual UTMB Eiger Ultra Trail we thought that we would plan our training around running the entire course. We knew that it was regarded as being one of the tougher UTMB World Series Events at 101km and a total elevation gain of 6700m. So being sensible we thought that we would run the route over 5 days rather than sticking to the official time limit of 25 hours. After all, it was supposed to be a running holiday so we really wanted to enjoy the training without any time pressure. However, soon enough we discovered what makes the Eiger Ultra Trail truly one of the most difficult UTMB events around. And by sharing this somewhat cautionary tale I can now pass on some of the hard lessons learnt about trail running.

EUT sign

Day 1 Grindelwald to First Station 

Distance: 24.21km Total ascent: 1,941m Time: 5hr11min

EUT elevation 1

On the first day we were off to a relatively early start but we were absolutely bursting with energy and ready to take on the Eiger Ultra Trail. We knew that it would be one of the most difficult days with several steep climbs to conquer, many of which we had literally skied down last winter. We had no idea what kind of terrain had been hidden underneath all that snow. But at least the first part of the route only consisted of a very rocky, loose, uneven trail. No problem, I thought. I was wearing my new trail shoes and they could contend with anything. Well, anything that is except for sheer clumsiness and total ineptitude because after running only 2.5km I tripped and fell hard. I had not only cut open my left knee and had two heavily bleeding deep dents but my right hand was also cut up and swollen.

Luckily the soft water bottles in the front of my running backpack had worked as quasi-crash bags and prevented me from completely face-planting. The water bottles had also helped to prevent my phone from smashing. However, my ribs did the heavy lifting instead and took the full impact of the phone as I fell onto the ground. They were badly bruised and possibly fractured although I hadn’t fully realised it at the time because my gaping knee was getting all of my attention.

EUT route 1

Never mind. At least I had had the foresight to have packed an emergency kit. It was unused and had been originally made up for a long forgotten event many years ago. Since then it had simply been popped into my backpack without another thought whenever I ran a self-supported event. However, upon finally cracking it open I soon discovered that it was more geared towards surviving wet and wintery weather. So it was fantastic for riding out a snowstorm but did not contain anything that could contend with a paper cut let alone stem heavy bleeding or patch up a deep wound.

Fortunately, my husband’s recently restocked emergency kit was far more appropriate for the job at hand and we managed to hold the knee together with an ugly assortment of plasters and tape. It might have looked like a bit of a bodge job but it simply had to do because we had a very long day ahead of us and we were in the middle of the countryside. Besides, we weren’t entirely sure of the Swiss protocol of how to call an on-duty St Bernard rescue dog to stitch me up. Throughout the day, however, I had to keep changing the ‘dressings’ and as I got sweatier and dirtier they flapped like sails in the wind. Which brings me to the first important lesson I learned about trail running.

Lesson 1 – Always check beforehand that your emergency kit is suitable

Day 2 First Station to Schynige Platte 

Distance: 22.69km Total ascent: 1,284m Time: 5hr38min

EUT elevation 2

After a first difficult day I knew it was going to be even harder now that the adrenalin from the fall had worn off and had been replaced by pain. But armed with the wise words of the local pharmacist and a fat wad of Switzerland’s finest Steri-strips and bandages I was ready to take on Day 2. I decided to swap my stiff trail shoes for my most comfortable road trainers as I thought that their extra cushioned soles would help me cope better with my bruised and battered body. I also knew that they’d worked perfectly well running on muddy cross-country trails. As we sat in the gondola riding up to the top of First my toes really did feel quite cosy. However, as we headed off from the station it soon became clear that my pillow-like shoes were no match for the rugged mountain terrain ahead.

The Eiger Ultra Trail, officially the E101, is entirely off-piste and routed over the most beautiful but extremely challenging and treacherous terrain. You run on the most uneven, undulating, rocky and root-littered, narrow paths that are also extremely steep and perilous. Since the route constantly changes direction and has plenty of hairpin turns you never know what kind of terrain you’ll face around the corner. The trail also snakes around high cliffs with such mammoth drops that some areas are lined by a fixed bungee cord to grip for safety. All of this makes it really difficult to get into a consistent running pace or to estimate your timing because you cannot base it on pure distance. Especially because despite the E101 being signposted by white and red striped rectangles painted onto rocks and trees it is still easy enough to make a wrong turn and go even further off-piste. In retrospect it’s glaringly obvious that trying to run it wearing anything other than good trail shoes is a massive mistake.

EUT route 2

I quickly discovered that my road trainers lacked the bare essentials of a basic trail shoe. Which meant I had to rely on my good hand to cling onto rocks and branches to climb anything steep or slippery to stop myself sliding off course. My shoes’ lack of grip also made it very difficult to slow myself running down any steep descent. It turns out that flailing your arms out and flapping them doesn’t really help you slow down either. My comfy trainers also lacked the firm midsole of my sturdy trail shoes so I felt every single sharp stone, knobbly root and knotted tree branch I stepped on. I spent the entire day hopping about trying to run on the smoothest part of the path yet mostly getting it wrong.

However, what I regretted the most about wearing my trainers was not having any reinforced toe protection. Every time I kicked something or had to squeeze my feet between narrow rocks and sharp crevices I really felt it. Not to mention, every loose rock that fell onto my toes. To make matters worse, as my trainers are very breathable they also let in copious amounts of dirt and sand which when mixed with sweat created the perfect conditions for blisters. I might have had to learn this second lesson the hard way but now you don’t have to.

Lesson 2 – They’re trail shoes for a reason so wear them

Day 3 Schynige Platte to Wengen

Distance: 19.99m Total ascent: 985m Time: 4hr53min

EUT elevation 3

As I laced up my trail shoes and packed another freshly stocked emergency kit I started Day 3 feeling more confident about what we would have to conquer. I knew that today we were going to have to start from the Schynige Platte at over 2000m and get down a very steep descent to Burglauenen at 898m. We would then have to travel up again and around the opposite mountain in order to reach Wengen. Looking at the map I expected that at least the first part of the morning we’d be taking a break from some of the difficult steep climbs. Alas, it was not to be. The Eiger Ultra Trail literally makes a mountain out of any molehill.

Rather than just heading straight down we found that we actually headed up for quite some time on rocky verges and rolling hills. It wasn’t until the end of the morning that we finally felt we were actually running downwards. And there were plenty of other surprises in store that day.

EUT route 3

Starting with a particularly rocky trail where we suddenly came to an area with some old barrier tape hanging off of a tree. But we confirmed that we were still on the E101 and couldn’t see any other way down so we decided to carry on. It was a very sketchy, technical descent and we came down along with plenty of tumbling rocks until reaching the bottom of a steep scramble. We then saw a sign and more barrier tape secured across the route and found that this section was closed due to the danger of falling rocks. The UTMB event 2 weeks previously had included an earlier detour to avoid this area but somehow we had completely passed it by.

We were also surprised to have to get up close to so many cows as they grazed and lazed about sleepily and blocked the route. Although by Day 3 we were adept at dodging cow pats, coming face to face with these massive beasts is a different thing. When a cow is taking refuge in the shade from temperatures upward of 30C and leaning against the gate you need to pass you have a problem. Unless you are lucky and it is receptive to a little gentle persuasion then your only choice is to go off piste and be thankful that it isn’t a bull.

Luckily, not all surprises are bad. As we headed up a steep mountain path in the second part of the day my legs were shattered and I was feeling spent. But as the sky started to darken and we sensed a storm brewing, our map told us that we were in the middle of nowhere. After a few tentative drops the rain suddenly poured down in an enormous summer shower. We just tried to climb as fast as we could to get somewhere, anywhere that we could shelter. As we rounded a corner at the top of a hill we could just make out some trees in the distance and also a goat farm. We ran soaking wet and miserable but as we got closer we could see several hikers sitting at covered tables with some coffees. The farm turned out to have a pop-up café and since it didn’t exist on any map or GPS it was the best surprise of the day. There is nothing like having a warm coffee and a snack to wait out the weather and to fuel you to the end of a run. Which brings me to Lesson 3…

Lesson 3 – Always be prepared…but expect the unexpected

Day 4 Wengen to Eigergletscher

Distance: 19.31km Total ascent: 1,776m Time: 4hr19min

EUT elevation 4

We started Day 4 at the ski town of Wengen by running towards the base of the gondola station. As we craned our heads upwards and looked at the gondola floating high up to the top of the mountain it was clear that we would be starting with one hell of a climb. The Eiger Ultra Trail was routed straight up to Mannlichen at over 2225m but by then we were no longer intimidated by such ridiculous climbs. After all, how much harder could it be than anything else we’d faced on the E101? Well, it turns out that if you add in a bit of bad weather, quite a lot.

Although it was still very hot and humid it soon started to rain relentlessly and the rocky trail became water-slicked and slippery. It was increasingly difficult to climb upwards while avoiding the deeper puddles and boggy patches, but up we went. We seemed to the only people crazy enough to try to climb up to Mannlichen in such conditions because as we passed several hikers travelling downwards, many wished us ‘good luck’! After some time we finally managed to make it to the top completely waterlogged and knackered. At least we could take shelter at the welcoming berghaus where we fuelled up and made use of the restaurant’s hand dryers to dry our jackets and tops.

EUT route 4

We had to quickly set off again as we had to run some distance before we planned to stop for lunch. As the weather started to clear up I thought I’d tie my jacket around my waist to dry off further. Of course, the clouds immediately opened in another downpour and by the time I managed to zip myself up again it was too late. At least the route became slightly smoother as it cornered the mountain and we quickly took the chance to get into a good pace. We kept passing more groups of wet hikers who were walking in the opposite (and easier) direction to us. But we must have looked quite a sight because as we passed some of them started clapping!

By the time we made it to our planned stop in Wengernalp the rain had stopped again and the sun came out in full force. We had to quickly slap on the sun cream but it wasn’t to last because just as we made our way again it started to cloud over. The timing couldn’t be worse because we were about to begin the last leg of the journey which was an epic climb up to Eigergletscher at 2320m.

It was absolutely brutal and like many other parts of the Eiger Ultra Trail, it was also mentally very challenging. Once again, our final destination was in clear sight but the route to get there was not the least bit direct. Instead it involved a long wet descent on a flooded woodland trail full of trip hazards before the route veered up sharply. It then became a very narrow rocky ridge with a high drop on both sides that seemed almost suspended above the ground. It was extremely steep and slippery and by then the weather was getting even worse. It was absolutely chucking it down and was so windy that it was raining sideways. I literally felt like if I made one wrong move I would be blown off the mountaintop. It didn’t help that the rain managed to permeate the one part of my body that wasn’t 100% waterproofed and so soaked me to the core.

Once we finally reached Eigergletscher I was absolutely drenched and shivering. Sadly, although I had had the sense to pack a warm dry top in a waterproof bag to layer on, the extra socks that I had tucked into my pocket had soaked up the rain like two fat, heavy sponges.

Lesson 4 – Be prepared for all weather

Day 5 Eigergletscher to Grindelwald

Distance: 19.89km Total ascent: 688m Time: 3hr55min

EUT elevation 5

It was the final day of the Eiger Ultra Trail and although we were very tired we were excited to start the day by running around the base of the Eiger North Face. The trail was now a steep rocky path that seemed to be carved out of the side of the mountain. As we ran along the route we passed several memorials to climbers who had died trying to climb the Eiger. Looking up at the immense wall from the base it truly looked like an impossible feat. Just getting around the base of the Eiger was proving to be intimidating enough as the narrow route was bordered by an incredibly deep drop to nowhere.

As today’s leg would involve heading down over 1300m to the finish we knew that it would have to involve plenty of downhill sections. And at first the Eiger Ultra Trail did not disappoint as we ran down for several kms while having to negotiate some tricky steep sections. But as we ran down even further and got closer to Grindelwald I began to have a sinking suspicion that this was too good to be true. Of course it was because at the end of a very long descent we then had to climb right up again to almost the same elevation that we had started from. Although we were used to some of the mind games the Eiger Ultra Trail seemed to be playing with us by the end of 5 days running it felt like torture. Again and again we went down further but then back up even higher and we very slowly zigzagged our way to the bottom.

EUT route 5

Once we finally reached the bottom of the valley we knew that there was just one short climb left before we could run to the finish in Grindelwald. But short doesn’t mean easy because although the trail went up a tarmac covered path it was steeper than anything I had ever seen before. Up I went sweating and grimacing, determined to get to the top until I could finally stop to catch my breath. Rather strangely, the summit was in the middle of the high street full of people milling about shopping and relaxing in outdoor cafes. We must have looked a messy, dirty sight but we tore down the street with big grins on our faces. As we finally reached the finish at Grindelwald station and stopped our watches I was absolutely overwhelmed with relief. We had actually made it!

Lesson 5 – What goes down must come up

Total distance: 106.09km Total ascent: 6,674m Total time: 23hr56min

In the end, we managed to complete the UTMB Eiger Ultra Trail in under the official time limit of 25hrs but I am under no illusion that I could have done the event in one go. It is probably the toughest running holiday that I have ever been on but I loved (almost) every minute of it. It did take me several weeks for my knee and ribs to heal but it was still worth it and pushing myself outside of my comfort zone. It may have been a baptism of fire but I learned a lot about trail running and have definitely become a more confident runner. Most of all it was a good reminder of the amazing sense of achievement you can get by challenging yourself. Hopefully by sharing these lessons I will save you some trouble and also encourage you to give trail running a go.


Suzanne Anderegg


I am originally from Canada but I settled in the UK after studying at university. Sports have always been a part of my life and I have participated and competed in several throughout my childhood. But today I would describe myself as mostly a runner, a mother of 3 grown-ups and a keen cook. As a teenager I was a sprinter and a slightly reluctant cross-country runner but while my children grew up I started to run further and further distances. I never thought that I could ever run anything longer than a half marathon but when my runner husband decided to do a marathon for his 50th in 2019 I found that I had a serious case of FOMO. My children encouraged me to sign up for my first marathon and I ran it just to see if I could finish. Somehow my time was good enough to qualify for the Boston 2020 Marathon. However, due to Covid it was postponed several times.

Like many other runners, I spent much of my time in the Covid lockdown keeping up my fitness by participating in virtual races while waiting for the real events to start up again. As time went on I found myself becoming fully immersed in the world of endurance running and ran the Threshold Trail Series ultra, Race to the Stones. Unfortunately, by the time the Boston Marathon was finally held in late 2021, I could not go because US travel restrictions were still in place. Although I missed my chance to run it and will now have to requalify again at least my time spent keeping in good shape wasn’t wasted. These days I participate in everything from half marathons up to ultras and have also run the Great Glen Way and West Highland Way in the Scottish Highlands.

I also work as a Registered Nutritionist with children and families and founded the consultancy Just add water® in 2019. I write a blog at to give free information and advice about nutrition and running whilst also sharing some of my favourite healthy recipes. The website is mainly aimed at busy families who want to make easy to prepare meals that are both healthy and really tasty, and for active families who want to know what they should be eating before, during and after playing sport.

I have always enjoyed cooking and previously cooked as a profession and I like to share my passion for good food. I have been involved in teaching cookery in schools, children's centres and for the NHS. I also enjoy entering the odd competition to push myself out of my comfort zone. I was awarded Highly Commended at the Teflon™ Diamond Standard Awards 2020 national culinary competition in the category of Keen Home Cook and was a National Finalist in 2022 & 2019. I have also had my recipes published in The Guardian's supplement, Cook; and featured in the 2012 Waitrose LOVE life calendar (July); and selected for inclusion in the 2020 #AnyWhichWayaBix Weetabix recipe book.

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