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Klaas Willems' story

Author: EN: Mar. 7, 2017. Klaas Willems


Yosemite has always been this place I wanted to go to but never thought it would be possible. The walls too high, protection too bad and my health would never allow it. 

I was born with cystic fibrosis. To stay as healthy as possible it helps a lot to do sports so in 2004, at the age of 18, I started climbing.

Cystic fibrosis is a genetic disease that effects the whole body, mostly lungs and digestion, and gets worse as you get older.
Over the years they found lots of medication to slow the effects of CF down, but never stop them.

When my sister and I were born the doctors told our parents we would never reach 6 years old, later it was 12 and now the average life expectancy is around 37. That’s why CF patients need to do sports and live healthy. To try and fight as long as possible and hope that the treatments improve in the future.


When I started climbing, Yosemite was always this far away dream. The first step was to go climb outside. I went with some friends to Freyr, a climbing area in Belgium, known to local climbers as the centre of the universe. The climbing there is very technical and crimpy. It’s bolted but on some lines you wished it was trad so you could place gear in order to avoid the long runouts. Adventurous climbs that are both mental and physical. Clipsticks are only allowed to put your jacket on.

For my 20th birthday my father, also a climber, gave me this climbing course as a present. The person giving this course was Sean Villanueva O’Driscoll, who just got back from his first trip to Patagonia. I had no idea who he was and why he always needed to play on his flute. But apparently he knew how to climb and how to motivate people.

On my birthday he put the quickdraws up a 7b for me and 2 tries later I climbed my first 7b and really started to get addicted to climbing and the outdoor lifestyle. It also made me realise that I could still do lots of things despite my health problems.

 I will always remember this trip for many reasons. One of them is that Sean still takes all the credit for my climbing progress over the years because of his brilliant flute playing and motivational screams and shouts during this trip.

Sean also talked about Yosemite and his first time climbing there. Yosemite was still a faraway dream but there were other dream lines to climb in Freyr. Cool cat, a 8a+ for Freyr standards that I looked at every time I walked by and hoped to climb it one day.
6 tries later I sent it and this is still one of the best lines I ever climbed. For the people that never have climbed in Freyr the style is vertical, technical climbing using footholds as handholds and glass as footholds.  

What should have been a happy moment was shadowed by the hospital visits during this period. I was told that if I would not change my lifestyle (I was living in the city, studied and did not make enough time to do all my therapy) my life expectancy would be 6-7 years.

This was for me a big wakeup call and I started to focus more on my climbing, being in nature with clean air. Also taking more time to do all my therapy would become my job and I quit my studies.


It all worked and I got proof of this by doing Esperanza, an 8b+, left of Cool cat. This was a bit of a sign that I should start to think that Yosemite could be more than just a dream.

My friend Mich wanted to go to Yosemite in 2009 and motivated me to go and check it out so we booked our flight. I arrived in Yosemite with not so much preparation. I never climbed a multipitch, never climbed trad, and never climbed in the dark.

The first day there I lead climbed the 2nd pitches of Serenity crack in the dark and it felt good to tick off all those things in the first climb only one hour after we arrived in the valley.

Mentally I was a bit overwhelmed by this place and I realised that coming here with no alpine experience at all was maybe a bit too much.

The first time I fell on a cam I placed myself for protection I screamed like a little girl. Taking 15m victory jumps from the anchor on sport climbs were totally fine but a fall 15cm above a cam felt like absolute horror!

First we climbed the Moratorium and then we had to come down Astroman after the Harding slot. I was sick for 2 weeks after pushing my body a bit too much.  The smartest thing to do after this was go climb Freerider on El cap no?

Halfway up the wall Mich lead climbed the monster offwidth and I had to follow. For those who don’t know offwidth climbing: it’s a climbing style that resembles a lot like Don Quixote fighting windmills.

You have a battle with a granite crack that is too wide to jam your hand for climbing up and too small to climb inside it like a chimney. The monster offwidth is 50m long and is trying to spit you out the whole way up.
Don’t ask me how I did it, but I got to the belay without falling but I was so destroyed, mentally and physically. I was coughing more and more and my whole body was giving up.

After some more climbing I had to admit that this was all too much for me at the moment. Mich understood and we went down.

I told Mich that if he wanted to climb Half dome and El Capitan he should find another partner because I knew It was too hard for me. Hopefully I would be strong enough next time to be able to climb them myself.

I realised that If I wanted to enjoy the climbing in Yosemite I needed to have a bit more experience with this style of climbing.


The next years I focussed more on climbing in the mountains and in 2012 Tim Teerlinck and I booked our flight to Yosemite.

In the summer I climbed a lot in the mountains to prepare myself. With my father I climbed the famous “Traversée de la Meije (3987m)” in the alps, the dream line of my father.

We got stuck in a storm after the summit and 27 hours of climbing and a shivering bivi later, we got back to the mountain hut.

During this climb I felt my heart beat very strong and thought that the altitude was more of a problem than usual for my lungs but knew that in Yosemite we would never climb so high.

Tim and I climbed the Dibona a couple days later and then went home to Belgium to prepare for Yosemite.


Every time before a bigger climbing trip I go 2 weeks before to hospital to see if my health is good enough for it. If it’s not, I need to go 2 weeks to hospital for antibiotics and normally after that I get better.

The normal check-up in hospital is doing a lung test and a picture of the lungs at radiology. When the doctor came back with the results It didn’t look good. There was something on the lung radiography that alarmed the doctor and he thought it could be cancer.

10 years ago I already had cancer so I knew what this could mean. Sadly enough the doctor was right.

Yosemite was again a distant dream and the surgeries, chemo and radiation were the hard reality that kicked in.

I knew now that the reason for my strong heartbeat on the mountain was that my heart just didn’t have enough space to beat because of the lymphoma.

Every CF patient can tell you that in our life we have to deal with sickness and pain so many times that we don’t really think to go to a doctor when we aren’t feeling so well.
It’s just so normal to not feel good that I never thought to go to a doctor to go and check for this heartbeat.

Afterwards I heard that this could have gotten so bad that my heart would not have had enough space to beat and that this would have killed me.

The next half year was a period of having surgeries, chemo sessions, vomiting while lying in bed at home or in hospital and after some more weeks radiation.

Hodgkin’s is a treatable cancer so that was a bit of a positive thing. The biggest problem was the treatment. One of the 4 chemotherapies, called bleomycine, is very bad for the lungs and the radiation was on the lungs as well.

My last chemotherapy was on December 31st. I was hospitalised at that time and found it funny that I was on drugs and vomiting when I heard the fireworks from the city while lots of people were doing the same over there.

On February 14th I had my last radiation but couldn’t find any reference to valentine here. 


It wasn’t easy to get better and it was hard to realise the treatment took a lot more from my body than I expected. The chemo and radiation made my lungs a lot worse.

 I had to make so much more effort to train and to get better but Yosemite was still in my mind.

I kept on climbing in the mountains because I knew that doing sports in clean air would help me a lot to get better again.

The endurance was a big problem so together with Ruben Beckers, Francis Collins, Tim Teerlinck and Jan de Smit we trained for the 20km of Brussels to raise money for the Cystic Fibrosis Organisation.

Two days after my 29th birthday we all finished the run.  All this training helped a lot for my health but I needed to make a lot more effort than before to get the same results. 


I got more and more confronted with the fact that I can try as hard as I can possibly try, yet my lungs will still get worse. This fight with CF is one that, sadly enough, we all know who will be the winner.

The reason why I’m writing all this down is because I’m again in hospital. This time it is after I got back from Yosemite.

In September 2016 I took the flight to Denver to meet with Cat. We were going to make a road trip, climbing in many places and end in Yosemite where we would meet with Raffa to climb there until the end of the trip.

Five days into the trip, driving out of the Black Canyon where there was no phone reception, I got the bad news. My sister Jolien passed away after fighting 32 years with Cystic Fibrosis.

Nobody thought it was going to go so fast. Her body couldn’t fight it off anymore. I took a flight back home to be with my family and arrange the funeral.

Jolien was always proud of me for doing so much sport and therapy. She was happy I could have this outdoor lifestyle, even with all these health problems.

Since she was born before me she always had it harder. Part of her lung was removed at the age of 6, double lung transplant at the age of 20.

I grew up and always saw what CF can do to your body and this motivated me a lot to do sports to fight this disease with all that I could.

It’s very hard and also challenging to see your sister pass away because of a disease that I’m struggling with myself.  Also because I could never get close to her and had to wear a mask to not pass my bad bacteria to her.

Cystic fibrosis is a genetic disease so there are more CF siblings that know what I’m speaking of.

Insurance arranged my flight back to the U.S. after the funeral. I felt I had a responsibility to my sister and to myself to go and climb something in her memory.

I missed her last days because she wanted me to go there. I wasn’t only climbing for myself anymore. If this is what Jolien wanted me to do, I have to climb and enjoy every moment on the rocks.


Cat and I decided we wanted to climb Regular North West Face of Half dome.
In 2015 there was a big rockfall which made free climbing the line impossible. We would need to aid climb some parts, but neither Cat or myself had any experience in this.

Stepping into the unknown is fun but also a bit stressful. The day before we were going to go and try we realised that none of us knew how the follower had to ascend out from a rope swing. A good preparation is half the battle, no? A good start, indeed!

Luckily Cameron, a friend and climbing ranger, explained to us how to do this by putting some ropes on trees in camp 4.

He also told us we should do it in a single push from the valley floor and not to bivvy at the base of the line. He was confident we would be able to do this. Well, we were not!
But the Belgian standards have been raised a lot since Nico and Sean started to give masterclasses in an alpine environment.

I’m also a bit of a lazy person whenever it’s possible. Doing it in a one day push would mean not bringing sleeping gear and food so that meant less weight to carry. If I would wake up a bit earlier and do my medication before we climbed and be back the same day to do the aerosol again in the evening, it would all be ok.

Planning was done and we went to bed early. I woke up at 3.30 in the morning and started to do my therapy. I went to Cat’s tent after but she was still sleeping. There were some guys talking late about climbing half dome in a couple days and made too much noise so she had almost no sleep at all. She only had one more day in the Valley before driving back home so she wanted to go for it anyway. Around 5 am we started to walk from mirror lake to find our way in the dark to the base of our climb.

We never did this approach either but friends told us it was easy to find. Little did they know, I already get lost while following a GPS…

Also calling the approach line “the death slabs” weren’t too encouraging but after walking wrong a bit here and there we made it to the base of the climb.


We had some breakfast and waited a bit for the 2 people in front of us that only just started to climb. When they were a couple pitches up we started to climb too around 8.30am.

The climbing went well and we quickly got behind the other team. We had some chats, got to know them a bit. They were 2 young mothers that decided to go climb a bit again.

Proving that alpine climbing should not stop when you have a family lifestyle… big respect!

They let us pass them after the Robin’s traverse, halfway up the wall. This was just where the rockfall in 2015 had happened so we hoped we would not slow them down figuring how to do that part.

If one of them is reading this… well… sorry :) It took a little bit longer than we expected. we had to choose between 2 options. The knot toss or climbing higher and swing over.

I chose to do the swing but thinking about this after I would not recommend it.

Every time you swing the rope cuts over a very sharp corner so there is only a limited amount you could try this or the chance that the rope would cut is very possible.  

The main reason why I tried this was to try and avoid the anchor lower with what looked like a wasp nest. I got attacked by one a week before and got some stings and after realised I was allergic so I did not want this to happen again.

We climbed higher and at the bivvy ledge Big Sandy we saw another problem. Those wasps or flies, there were hundreds in the cracks we needed to climb. I got into stealth climbing mode, climbing as slow as possible to not get stung.


I told Cat to be ready to lower me fast if I got attacked. I wished I knew what I know now, that those were just flies that looked like wasps…

Anyway, It was not fun to climb and feel those flies around your fingers every time you jam them into the cracks.

I got to the last anchor before the top and suddenly heard a voice saying “one, two, three… see ya!”. A wingsuit guy jumped right over me and rocketed to the ground. He flew off in style and we gave him the proper monkey calls during his flight.

One pitch later we arrived at the summit with the most beautiful sunset I had seen in a long time. I walked to the spot where the guy just jumped off and while the last rays of sun warmed me in this magical moment in a magical place I let the ashes of Jolien free.

Only one month after her passing I was standing here and she was with me during the whole climb. Cat was the person with me when I got the news of Jolien’s passing.
I had a lot of help from her at that time being so far away from home. It felt right that she was here with me at this time as well. 


It felt like an obligation to my sister that I climbed Half dome. Knowing that last time I was here I did not feel ready at all to climb it. I have survived cancer and found the energy to get better to be able to do this.

A reason for this is my sister’s motivation and admiration for my lifestyle. She isn’t here anymore to help me.

In my mind she’ll never leave and I hope I can keep climbing mountains for many more years before Cystic Fibrosis wins the fight with me too.

The only thing I can do is keep my body as good as possible. I have seen the side effects from antibiotics and other medication with myself and my sister.

There are no side effects from doing sports. Clean air and a healthy lifestyle are a must for everyone, not just CF patients. I’m not saying I can go without all my medication. Just that with a healthier lifestyle I will not need to take it so much and that when I really need it, the bacteria are not yet immune to the antibiotics and my kidneys will still be able to clear my blood from the bad side effects from it.

Don’t read this as me telling everyone how to live their lives. It’s just my opinion how I want to live my life and felt like sharing this to maybe motivate others to live more healthy and do more sports.

Klaas Willems