Gravmageddon 2023: Karkonosze - Izery Gravel Race


August 11, 2023☕️☕️ 8 min read 18

Ultra gravel racing is something I have wanted to try for a long time. Welcome to the recap of my first (and hopefully not last!) ultra gravel race - 2023 Gravmageddon.


Gravmageddon is an ultra-endurance race in the Karkonosze and Jizera Mountains. It offers many climbs, serious elevation gain, and some awesome gravel sections that can unexpectedly change into challenging rocky paths. The 360km long route with 7,600m of elevation gain guarantees satisfaction at the finish line.

Most riders will try to cycle the lengthy route in one go, with breaks only long enough to resupply and eat non-gel food at pitstops or grocery stores. The extensive distance forces you to cycle at night along remote, gravel roads and singletracks in the mountains. The strategic choices riders have to make, along with the physical demands and stunning location in the Karkonosze Mountains, create the race’s unique allure and make it so fun to race.

Race Route

Gravmageddon 2023

  • Distance: 360km
  • Elevation: 7400m
  • Time: 30 hrs
  • Date: Aug 2023

Gravmageddon 2023 was definitely a fight against elevation gains and steep climbs. Instead of thick off-road tires, a proper climbing gear ratio would be more useful - at least this is what I realized during the race while fighting steep climbs with my 11-34 cassette …

Climbing Highlights

The 30 Hours of Racing

The race had a rolling start. From 6am on, every 5 minutes, a group of riders would start. My friend dude cycling and I managed to secure early slots with the 6.20am group so that we could maximise cycling in daylight. The race started in Szklarska Poręba, and after a short uphill, we quickly got onto Droga Pod Reglami, which led us to the hardest climb of the race. Upon reaching the steep section of the road to Karkonosze Pass, I realised two things. Firstly, the stock GRX 11-34 cassette is not suitable for climbs like that, as I had to push the pedals much harder than I had wished. Secondly, most riders carried less stuff; at first I was surprised by their choice, but then I understood that we might have made a strategic mistake by fully loading our bikes at the start.

Gravmageddon offers pit stops at 95 and 270km, where you can send equipment to wait for you later in the race. For example, instead of riding and climbing with all of our night gear in the saddle bags, we could have sent it to pit stop 1. We’ve just sent our food, and it was not an optimal decision. The right strategy can make races like this at least a bit easier. That’s my lesson for the future.

After reaching the Karkonosze Pass, we descended on a fast tarmac road into the Czech Republic. Around 70km of good tarmac and light gravel roads led us to pit spot 1 on Polana Jakuszycka. At this point, we’ve already had 2700m of elevation gain in our legs. We resupplied, ate fruits and some proper food, and naturally chilled a bit with coffee ☕️! Ahead of us, we had 270km with a looming climb to Jested in Liberec.

Rolling hills, going up just to go down, are the only things I can recall from the next section. I only “woke up” near Liberec when we started the big climb to Jested.

At the top of Jested, there is a famous tower and a viewing spot. The climb is perfectly suitable (and probably more enjoyable) for road bikes. We stopped there for a while to stretch, catch a breath, and dress up before the long descent.

The night caught around the 250km mark. It was a beautiful part of the route. It included the Smedava climb with a cloudless sky full of stars. The road types changed from gravel and smooth tarmac to bumpy single tracks and rocky mountain paths. Riding on singletracks at 1am on my loaded gravel bike worked better than coffee. The rush of adrenaline on fast technical descents gave me an energy boost to reach pit stop 2 around 3am. We’ve had 290km and 5900m of elevation gain so far.

Around the 300km mark, the forecasted heavy rains hit us, and the apparent temperature, as reported by my Wahoo, dropped to 6 degrees Celsius. The weather, along with especially rocky paths, made the last section seem like a never-ending task. We rode quite slowly and had to stop for the famous pancakes at Chatka Górzystów just to be able to make it to the end. We reached the finish line cold, wet, and full of mud, but extremely happy to participate in such an amazing event.

All in all, I enjoyed the race route a lot. Shoutout to the race organisers for their awesome job! Also, I’m a huge fan of the Gravmageddon cycling cap design. In the front, you can see “Wytrwajcie do końca wy konie” which roughly translates to „Keep it up till the end”. And the pattern that goes around the head depicts the race’s elevation profile, with notable climbs.

Crossing the finish line with dude.cycling.

Strava activity for anyone interested.


Here’s a great video from the race organizers that captures the vibe of the event:

My Bike Setup


I raced on my trusty Canyon Grizl AL 6 with 45mm wide tyres, running tubeless, and a standard 2x10 GRX 400 groupset: 46/30 crankset and 11-34 cassette. My biggest takeaway from the race was that a bigger cassette is an absolute must for hilly routes.

I took this pic of my bike during a different trip in the Karkonosze Mountains. For the race I did not install the handlebar bag and my saddle bag was not packed as much.

Bags and Equipment

Given the unpredictable weather conditions and potentially cold night I decided to pack more things just to stay on the safe side. I used the following bags:

  • Ortlieb seatpack (rolled down and compressed) - It stored my rain jacket, Nano Puff jacket, base layer, leg warmers, gloves and Buff scarf. This bag proved many times to be completely waterproof, so I stored there stuff that had to stay dry.
  • Topeak 4.5L frame bag - I put there tools, TPU tubes, tubeless repair kit (It was useful!), food, powerbank and headlamp - anything that could get wet as this bag is not fully waterproof.
  • 1L Apidura top tube bag - I love it for its magnetic rivets to quickly access important stuff, I had my phone and documents there. This bag is waterproof.
  • 2 x 1L handlebar packs fully packed with food.


I used a Wahoo Element Bolt for navigation. I made sure to set it to the most energy efficient mode, as I wanted to avoid charging it during the forecasted rains. With the backlight set to “auto”, diodes turned off, my phone Bluetooth disconnected and just a single sensor: my chest strap - the battery life on a single charge was even more than the advertised 15 hours. The GPS navigation worked great, even in the mountains.

Strong front lamp with sufficient battery is a must when racing at night. I settled for a recommendation from my friend: a bike lamp from AliExpress with replaceable batteries. Surprisingly, I discovered that proprietary lamp batteries are readily available in Poland. For the race I was equipped with 2 batteries, each with 3350mAh, which allowed me to cycle through the night with the lamp set to 400 lumens. I can honestly recommend this lamp (Enfitnix Navi800) as a cheaper alternative to established solutions. Disclaimer: I have no affiliation with this brand.


En route.
Finish line.