The GR20, one of the most captivating and demanding hiking trails, requires in-depth preparation for an optimal experience. Not only is a robust physical condition necessary, but also meticulous mental and material preparation. Careful planning of your itinerary is crucial to fully appreciate this unique route. Before embarking on the GR20, make sure you have adequate preparation, a well-defined budget and the right equipment for this memorable adventure.

Endurance and physical preparation

Developing solid endurance is essential for success on the GR20. Start preparing several months in advance with regular exercises to get your body used to walking and climbing. Strength and endurance are major assets. Our advice on how to prepare physically for the GR20?

Choose the direction that suits you

The traditional GR20 route is designed to go from the north, from Calenzana, to the south, to Conca. However, there is no compulsory direction for walking the GR20. It is also possible to start from the south and work your way north. It is often said that the hardest stages are to be found in the north, so depending on which direction you choose, you will encounter them either at the beginning or at the end of your journey. Read our article on which way to walk the GR20.

Access and emergency exits on the GR20

Access for a classic GR20

For a classic start to the GR20, the traditional north-to-south starting point is Calenzana, near Calvi in northern Corsica. If you prefer to start in the south and work your way north, the starting point is Conca, near Porto-Vecchio. For those wishing to cover only part of the GR20, the central point of the trail is at the Col de Vizzavona, offering a convenient option for a semi-GR20.

Emergency exits and escape routes

Although the GR20 is an isolated mountain trail, it is crossed by several access roads. These points are essential for hikers wishing to have the option of a rescue vehicle. As well as the start and finish points, there are several intermediate points with road access: Calenzana, Haut Asco, the Col de Vergio, the Col de Vizzavona, the Ghisoni station at Capannelle, the Col de Verde, the Cuscionu plateau, the Col de Bavella and Conca. These points offer exit options in case of need and facilitate supply and rescue.

The essential choice of rucksack

For the GR20, choose a rucksack suited to the length of the trek, your independence and your personal needs. For the full GR20 (around 15 days), a 60-70 litre rucksack is ideal, weighing between 10 and 12 kg. If you opt to carry less, a 50-60 litre bag weighing between 8 and 10 kg is sufficient. For hiking without a rucksack, a 30-40 litre rucksack weighing between 4 and 6 kg is adequate. Make sure the bag is comfortable, adjustable to your body shape, and fitted with straps and a suitable frame. Choose a bag with practical, weather-resistant compartments and pockets, made from robust material, and with external attachments for extra equipment. Consider a bag that is compatible with a hydration system, and opt for a lightweight but sturdy bag. Testing several bags with different weights can help you find the most suitable model. Find out more about choosing the right rucksack for your hike.

Payment of drinks and other additional expenses

Payment by credit card is not an option available on the entire GR20 route, as this method is only accepted in a few specific types of accommodation. In addition, cheques are not always available. So make sure you take an adequate amount of cash with you to cover personal expenses, as there are no cash machines along the route.

Map, topo and GPS

The PNRC ensures that the GR20 trail is well maintained and signposted. To prepare properly for the trek, it is important to examine the route before setting off. We recommend that you have at least two different orientation systems to prevent any unforeseen problems.


A topo-guide detailing the route day by day is published by the FFRP and the Corsican Regional Park. By consulting a topo-guide, you will obtain information about the route and the refuges, as well as general explanations about Corsica, its fauna, its forests, the massifs crossed, the language, and so on. What's more, studying the next day's guidebook can be both useful and enjoyable! You can find this topo-guide on the website of the Fédération Française de la Randonnée Pédestre.

IGN maps

The topo-guides are complete and very detailed, but a good knowledge of an IGN map can also be sufficient. There are several maps covering the trail. Read our article on : Which map to choose for the GR20.

GPS tracks

For those who are more comfortable with new technologies, the use of a GPS can be useful. Using a mobile phone with downloaded maps is one option, but pay attention to battery life. When walking with our agency, you'll have access to our walking app.

Practical advice

Recharging a phone on the GR20 is difficult because of the limited electricity available. To save battery power, deactivate mobile data and Bluetooth and use aeroplane mode. Use the phone mainly for navigation and emergencies. Carry external batteries or portable solar panels, which you can attach to your rucksack to charge while walking.


Red and white markers line the route. Alpine variants are marked by two yellow lines superimposed. Breaks in the trek to reach villages and leave the GR20 are indicated by wooden signs and often marked by a yellow line.

How do you stay hydrated on the GR20?

The answer is simple: from natural sources! It's true that you can buy soft drinks, beer or bottled water in the refuges, but during the day it's essential to drink plenty of water (up to 3 or 4 litres depending on the heat). The springs on the GR20 are ideal places to fill your water bottles or camel bags.

Water and springs on the GR20

Water is available in all the refuges and most of the sheepfolds along the GR20. This water, which comes from springs on the mountain slopes, is generally considered to be drinkable without the need for boiling or treatment, unless otherwise indicated. However, water from streams, which is often seasonal, may require treatment, particularly if it is frequently used by animals or for bathing.

On the IGN maps detailing the stages of the GR20, you will find indications of springs and numerous streams, the flow of which varies according to the season. Access to water may be more difficult at the end of the season. On the other hand, at the start of the season, particularly in June, there is an abundance of water as the snow melts. It is crucial to bring an adequate supply of water for your hike, as water sources such as fountains and streams can dry up depending on the year and the period. Don't rely exclusively on the information on the IGN maps; also consult the hut wardens for up-to-date information. Ask them if water points will be available on your next stage to avoid any unpleasant surprises.

Bottled water and other drinks

Bottled water is rare in the mountains, but the two main Corsican brands are St Georges and Zilia. There is a canned drink called Corsica Cola, for those who like variations on the same theme! Corsican beer, or bièra Corsa, on sale in shelters includes Pietra, Serena and Torra. Wine is sometimes sold in bottles or by the bottle.

The perilous passages of the GR20

The GR20 is one of Europe's most demanding trails, with notable challenges such as rocky terrain and the risk of landslides. Key sections such as the Pointe des Éboulis and the Brèche de Capitello require rigorous physical and mental preparation. The trail includes technical sections equipped with chains for added safety, but requires great vigilance, particularly on slippery slabs and in scree areas. Proper preparation is essential to navigate this rugged, mountainous route in complete safety. Read our article on: The difficulties and dangerous sections of the GR20.