GR 20: route guide

The trail crosses the island's spine from north to south, staying mostly above 1,000 m and often above 2,000 m. It starts at Calenzana in the Balagne, passes through the Parc Naturel Régional de Corse, and finishes at Conca near Porto-Vecchio. The northern half is the harder one: more scrambling, steeper climbs and longer days between refuges. The southern half from Vizzavona is gentler and is the usual choice for a shorter trip.

There is no single official map for the whole route. The red-and-white GR waymarks are the primary navigation aid, and most hikers carry a 1:25,000 topographic map or an offline phone map as backup. Signage is generally good, but cloud, snow patches and route variants can hide marks.

The classic north-to-south direction starts with a long climb out of Calenzana and gets technical quickly. The Cirque de la Solitude, a steep and exposed section between Ascu Stagnu and Tighjettu, is the part most people ask about; it has been subject to closures and rerouting, so check current status with the park before you go. If it is closed, a variant bypasses it.

The middle section around Manganu and Petra Piana crosses open plateau country with lakes and shepherding huts. It is less technical but still remote, and the days are long. Vizzavona is the natural halfway break: it has a train station, so you can leave or join the route there.

The southern half runs through the Bavella massif, with granite spires, pine forest and shorter climbs. Many hikers rate the Asinau to Bavella day as the best scenery on the route. The final descent to Conca is mostly downhill and can be done in a morning.

The season runs from late June to mid-September. Snow can linger on high passes into June, and refuges outside the season are often unstaffed or closed. July and August are the busiest and hottest months; start walking by 7am to avoid the worst heat and to reach the next refuge before afternoon storms.

September is quieter and cooler, but the first autumn weather can arrive late in the month. Spring is not a reliable option for the full route because of snow and closed refuges. Whatever month you pick, carry rain gear: mountain weather changes fast, and summer thunderstorms are common in the afternoon.

Accommodation on the route is in mountain refuges (refuges de montagne) and gîtes d'étape, spaced roughly a day's walk apart. Most offer dormitory beds, and many serve dinner and breakfast. Some also allow camping nearby, but wild camping is restricted inside the park, so check the rules for each area.

In July and August, beds fill up and reservations are strongly advised. Outside peak season, some refuges run with reduced service or close entirely. Carry a sleeping bag liner, cash in euros, and a little food in case a refuge is full or closed. The park and the refuge association publish current opening information.

Bastia is the usual arrival airport, with Calvi as an alternative for the northern start. From Bastia, trains run to Calvi and to Vizzavona; the Bastia to Calvi train is the standard way to reach the north end, and Vizzavona has its own station on the Bastia–Ajaccio line. Fares are modest, and schedules are limited, so check times before you commit.

For the southern end, buses connect Bastia and Porto-Vecchio area towns, but they do not run every day. Conca itself is a small village; the nearest practical transport hub is Ste Lucie de Porto-Vecchio, about 6 km away. A shuttle from Conca has been suspended, so plan on a taxi, a lift, or a walk of about 1 hour 15 minutes downhill.

Vizzavona is the best place to split the route if you only have a week. You can arrive or leave by train without a long road transfer.

This is a serious mountain route, not a coastal walk. You need fitness for 6–8 hour days with steep climbs and descents, and comfort on exposed ground. The northern half includes scrambling where you may need your hands. Train on hills with a loaded pack before you go.

Pack light but bring the essentials: sturdy boots with grip, rain shell, warm layer, sun protection, at least 2 litres of water capacity, a headlamp, a first-aid kit and a paper or offline map. Water sources are not guaranteed on every stage, so plan refills at refuges and known springs. Mobile coverage is patchy; do not rely on it for navigation or emergencies.

Start early each day. Hikers in the refuges typically wake around 6am and leave by 7am, which also gives you a buffer if the weather turns or a stage takes longer than expected.