GR20: water, huts and stages across Corsica

The GR20 crosses Corsica from north to south through the mountains, from Calenzana above Calvi to Conca near Porto-Vecchio. It is known as one of the most demanding long-distance routes in Europe: rocky passages where you use your hands, few villages, and days that are short in kilometers but long in hours.

This post answers the questions that come back before each season, with OnTrace data read along the whole route: where to find water, where to sleep, how to split the days and how to reach the trail without a car. The sheet below is worked out again every day.

The GR20 at a glance#

• About 180 km, from Calenzana in the north to Conca in the south, depending on the variants.
• More than 10,000 m of ascent. The exact figures of the route above are in the sheet, worked out from the altitude of the ground.
• 15 to 16 stages in the guidebooks, often 5 to 8 hours of walking for 10 to 15 km: on the GR20, count in hours rather than kilometers.
• Two halves split at the Col de Vizzavona: the north, higher and more technical, and the south, a little gentler without being easy.
• The season runs from June to September. In June, snow can cover the north-facing passages. In summer, storms often break in the afternoon: start early.

Water: at every hut, rarely in between#

On the GR20, water is mostly found at the huts and shepherds’ huts. In between there are springs and streams, but some dry up in late summer, and the ridges have none. A hot day on granite slabs takes far more water than you would think.

1. Leave each morning with enough to reach the next hut, above all on ridge stages.
2. Treat stream water: flocks and shepherds’ huts are many along the route.
3. Trust recent reports: on OnTrace, a spring walkers report dry leaves the calculation of the longest stretch without water.

Where to sleep#

The park’s huts line the whole route, with a few shepherds’ huts, gîtes and hotels at the road passes (Vergio, Vizzavona, Bavella). In summer, book your nights ahead, in a hut or in a tent: places are limited and a booking is often asked for any night.

Splitting the days#

Here is a split worked out on these same places, with days of 8 to 16 km: each evening near somewhere to sleep, the hilliest stages kept shorter. On the GR20, a few kilometers of scree can take half a day: it is a starting point, not a schedule.

Camping and protected areas#

The GR20 crosses the Corsica regional nature park, where camping is regulated: it usually happens on the areas set out near the huts, not anywhere along the trail. Read the park’s rules before you go, and keep to the periods given.

The sheet lists the known zones the route crosses or passes near. Where nothing is drawn, nobody knows: it does not mean anything goes.

Getting to the GR20 by train#

The Corsican railway serves the middle of the route, which lets you walk the GR20 in two goes or leave it cleanly in bad weather.

• Vizzavona, halfway, has its station on the Bastia, Corte, Ajaccio line.
• In the north, the Calvi line joins that same line at Ponte-Leccia. From Calvi, Calenzana is reached by road.
• In the south, Conca is reached by road from Porto-Vecchio.

The stations within 5 km of the route:

Plan your own version#

Open the trace in OnTrace, then choose Duplicate this trace to get your own copy: add your variants, nights and supply points without touching the original. You can also download the GPX of the sheet for your watch.

Before each day, check the mountain forecast: on the GR20, storms and fog often decide more than the guidebook.

Route: © OpenStreetMap contributors, under the ODbL. Altitudes: IGN. Places: OpenStreetMap, refuges.info and walkers’ reports on OnTrace.

• GR20
• Corse
• Randonnée
• Itinérance