The GR20 is one of the most famous and demanding trails in Europe. Crossing Corsica from north to south over nearly 180 kilometres, it is renowned for its impressive total elevation gain of over 10,000 metres and its technical passages. If you're dreaming of taking on this challenge, meticulous preparation is essential. Whether you're an experienced hiker or a passionate mountain lover, this guide will help you get ready for the GR20 and live an unforgettable experience while minimising the risks.
The GR20: a legendary and demanding route
The GR20 is a hiking route that crosses Corsica from north to south in 16 stages. Completed in around 15 days, it is known for its technical sections, impressive elevation gain and sometimes harsh conditions. The trail begins in Calenzana, in the north of the island, and ends in Conca, in the south. Although the route becomes more manageable in the south, the northern section is particularly demanding, with steep and technical terrain. This challenge draws nearly 20,000 hikers every year, yet the dropout rate remains high — around 40% — largely due to the difficulty of the early stages.
Choosing the right direction for the GR20
It is important to think carefully about which direction you want to tackle the GR20. Although the route can be done in either direction, most hikers opt for the north-to-south direction. However, if you are setting off early in the season, it may be wiser to start from the south to avoid the difficulties caused by snow on the northern heights. From a sporting perspective, starting from the north is often recommended, as it allows you to finish on the more accessible stages.
What is the best time to go?
As the GR20 is a mountain trail, choosing the right time to go is essential. June and the first half of September are generally the best times to complete this hike. Avoid the summer period (July and August) as the heat can be intense and the trails are often packed with hikers. The heat also makes staying hydrated harder and increases the risk of dehydration. Late spring and early autumn offer ideal conditions to enjoy the scenery while avoiding the crowds.
Physical and mental preparation
The GR20 is a major physical challenge, and preparation must be carefully planned. To complete it successfully, you need a solid fitness level and be ready to tackle some highly technical ascents and descents. It is essential to train for several months before you set off. To do this, go on hikes in mountainous terrain with a loaded pack to simulate GR20 conditions. Beyond endurance, you need to condition your muscles by strengthening your legs, ankles and cardiovascular system through cardio and strength-training sessions.
Preparing your kit for the GR20
Kit choice is crucial for a successful GR20. Here are the essentials to take with you:
- Rucksack: A 40-litre pack is sufficient if you are not going fully self-sufficient. It should be light and comfortable, and must not exceed 20% of your body weight.
- Clothing: Use the three-layer system to regulate your temperature. Go for technical t-shirts, a fleece and a waterproof jacket. Don't forget sun protection — especially in Corsica, where the sun can be extremely intense.
- Footwear: Choose stiff shoes with a good grip and a thick sole. High-cut hiking boots are ideal for rough terrain. If you prefer lighter trail shoes, make sure they offer good durability, good cushioning and a toe cap.
- Hiking poles: They will be invaluable for relieving pressure on your joints, especially on ascents and descents.
Planning food and accommodation
The GR20 has refuges along the route, but some are unstaffed and bivouacking outside designated areas is prohibited. You will therefore need to organise your accommodation in advance. If you prefer to sleep in a refuge, booking ahead is strongly advised — particularly in high season — to avoid any unpleasant surprises. Some refuges offer hot meals, but you can also choose to go self-sufficient and carry your own food. In that case, it is essential to plan light, high-energy meals such as freeze-dried dishes, and to resupply at Vizzavone, the only resupply point on the route.
Tips for completing the GR20
Here are a few tips to make sure your GR20 experience is a success:
- Walk in a group: It is always more enjoyable and safer. Mutual support among hikers is a valuable asset when it comes to overcoming difficulties.
- Stay hydrated: Water sources can be scarce in summer, so fill up your bottles whenever you get the chance.
- Look after your feet: Massage your feet each evening, keep your toenails trimmed and apply cream to prevent blisters.
- Test your kit: Never set off with gear you haven't tried before. Do several long outings to test your footwear, your rucksack and your clothing.
- Book your refuges: If you are setting off during peak season, remember to book your overnight stays in advance.
The GR20 is a serious challenge, but with the right preparation it remains achievable. Good training, careful planning and the right kit will allow you to make the most of this exceptional adventure. The beauty of the Corsican landscapes — wild mountains, dense forests and breathtaking panoramas — will make the experience truly unforgettable. Follow these tips to prepare well for the GR20 and enjoy a rewarding and memorable hiking adventure.
