1. Journey and preparation
I travelled from Quiberon to Belle-Île-en-Mer by boat, departing at 7:45 am on November 1, 2026.
My objective was to complete the GR 340, following the coastal trails around the island in a single effort.
I undertook this challenge alone, carrying all my food, drinks and equipment from the beginning, without any external assistance or resupply.
2. Nutrition and hydration
I carried the following supplies for the entire journey:
- 3 bottles of Saint-Yorre mineral water (500 ml each), totalling 1.5 litres.
- 1 litre of isotonic drink.
- 15 energy gels containing 30 g each.
- 1 additional caffeine gel.
- 1 Sundy bar.
- 2 rice puddings.
I followed a regular nutrition strategy, consuming carbohydrates approximately every 30 minutes throughout the effort.
I did not refill my bottles or obtain any additional food or drinks along the route.
3. Equipment
I carried the following equipment:
- Headlamp, used during the final part of the route.
- Windproof jacket.
- Sunscreen.
- Anti-chafing cream.
- External battery for my mobile phone.
This equipment was intended to help me manage the changing weather conditions and the demands of a long coastal effort.
4. Trail conditions and scenery
Belle-Île-en-Mer offers spectacular, wild and beautiful coastal scenery.
The landscapes were magnificent throughout the journey, with breathtaking views of the ocean and the rugged coastline.
However, the trail conditions were sometimes challenging.
Some sections of the GR were difficult to identify, with paths that were not always clearly visible. Certain sections were heavily worn and trampled, seemingly following the high level of tourist activity during the summer.
Other parts of the trail had also suffered damage from storms, making progress more difficult in places.
These conditions required constant attention and sometimes made it difficult to maintain a consistent pace.
5. Physical challenges and finish
The final part of the journey was particularly demanding.
Despite my nutrition strategy, hydration proved to be a major challenge. I had carried a total of 2.5 litres of drinks, which proved insufficient for my needs over this distance and elevation gain.
I reached the finish severely dehydrated.
Nevertheless, I continued and completed the entire route, using my headlamp during the final part.
6. Lessons learned
Looking back, I believe I could have managed my hydration much better.
For a future attempt, I would consider carrying up to 5 litres of water and isotonic drinks, depending on weather conditions and opportunities for safe water supply.
This experience reminded me that preparation and hydration management are just as important as physical fitness.
There is always something to learn from an endurance challenge, and every experience helps us improve.
7. A personal connection with Belle-Île-en-Mer
Being Breton myself, this journey around Belle-Île-en-Mer had a very special meaning for me.
As I travelled along its magnificent coastal paths, the island brought back many childhood memories. There was something deeply familiar and emotional about these landscapes.
Belle-Île is a truly magical place: wild, beautiful, sometimes rugged and always captivating.
I loved its atmosphere, its natural beauty and its authentic character.
Beyond the sporting challenge and the time achieved, this journey was also a personal experience, reconnecting me with a part of my childhood and my Breton roots.
I will certainly want to come back one day and experience this wonderful island again.
8. Conclusion
Completing the GR 340 in 11 hours and 40 minutes elapsed time was a significant physical and mental challenge.
I am proud to have completed this solo adventure, carrying all my supplies and receiving no external assistance.
The demanding coastal trails, the challenging conditions, the lessons learned about hydration and, above all, the beauty of Belle-Île-en-Mer made this an unforgettable experience.
A sporting challenge, a personal journey and a beautiful reunion with my Breton roots.
Anne-Solène Daniel