Corsica may be an island, but it contains an incredible challenge. The Grande Randonnée 20 (GR20) is often considered Europe's toughest trek. It's a feat many dreams of doing, but it's not for the faint-hearted.

You can't just jump straight into it as a novice, and so this guide serves as a rough guide to working your way towards it.

Understand the GR20 Requirements

The GR20 stretches over 180 kilometres with significant elevation changes and awkwardly rough terrain. Preparing for it means you need physical and mental readiness. Fitness, navigation skills, mountain safety, and some climbing skills will be needed.

Essential gear includes sturdy boots, a reliable map, a compass, a first aid kit, and weather-appropriate clothing. These you can get early on, as they will help during training.

Climbing and Scrambling Elements

The GR20 is not just a walk; it involves sections that require climbing and scrambling. You need to be experienced in traversing through rocky paths, and some parts are equipped with fixed cables and ladders to assist in scaling steep sections. While technical climbing gear is not necessary, a good head for heights and a strong grip are essential. So, ideally, you will begin by spending some time bouldering at your local climbing gym. The reason this is the first consideration is because it's the most alien skill, and so it's something you want to do from the start.

Building Your Fitness Level

Improving fitness is going to be key. Start with regular cardiovascular exercises like running or cycling to build stamina. Although stamina will be more important than strength, it's worth having a minimum baseline of being moderately strong—this is particularly important when carrying a big backpack. Exercises like squats, lunges, and planks can help you build your foundational leg and core strength.

Start with Moderate Hikes

Begin with local trails offering varied terrains. These hikes should last 4–6 hours with moderate elevation gain. You can jump right into these, even if you've never hiked before. Examples include trails in national parks or local hills. Focus on building your hiking stamina and getting comfortable with your gear. Use these hikes to practice navigation skills as well, and once you find these getting easier and easier, you'll be ready to take on harder challenges.

Progress to More Challenging Trails

Next up is to tackle multi-day hikes with moderate difficulty. The Fisherman's Trail in Portugal is a great example, offering coastal views and manageable challenges. These hikes help you experience carrying a full pack and dealing with having to wake up and do it all again. They will build your know-how and build experience that is similar to the GR20.

Advanced Training Hikes

Once you've clocked in many hours of experience, you'll be feeling more and more ready. All that is left is to go on a couple of advanced hikes that are closer to the G20's level of difficulty. Hiking routes in Greece are great for simulating a similar terrain and ascent, but similarly, you could go to the Alps, too.

Focus on maintaining a steady pace and managing energy levels as things get tough. This is also your chance to speak to other very skilled hikers (or guides from self-guided walking holidays) that you may come across on these advanced routes and learn from them.

Conclusion

Of course, you will need a lot of planning in regards to the GR20 logistics in and of themselves, but this guide will have gotten you to a place where you're now capable of doing so. All that's left is the final preparations and learning about the GR20, and then going ahead and planning it, just like you have done on the previous hikes.