The GR20, officially the Grande Randonnée 20, is widely regarded as one of the most demanding long-distance footpaths in Europe, traversing the mountainous spine of Corsica from Calenzana in the north to Conca in the south over 180 kilometres and 15 to 16 stages. The northern half is significantly more technical, crossing granite ridges, boulder fields, and high-altitude cols that demand sure-footedness and a head for heights; the southern half offers slightly more forgiving terrain but remains strenuous throughout. Hikers begin in Calenzana, accessible by bus from Calvi, and end in Conca, from which a bus connects to Porto-Vecchio. No permit is required to walk the route itself, though overnight stays in the PNRC-managed refuges require advance booking, especially from late June to August when pitches and dormitory beds sell out weeks ahead. The trail crosses the Parc Naturel Régional de Corse and touches the highest accessible terrain on the island, including the granite spires above the Refuge de Pietra Piana and the Col de Verde at 1,289 m separating the northern and southern sections. The mid-point at Vizzavona is served by the CFC railway, allowing hikers to split the route across two trips or exit in case of injury. Water sources are available at most refuges and some springs along the route; treating or filtering all natural sources is recommended. Altitude, sudden afternoon thunderstorms, and rapid temperature drops are the principal hazards — a warm and waterproof layer is essential even in July and August. The GR20 rewards experienced hikers with some of the most spectacular mountain scenery in the Mediterranean, including views across to the Italian mainland on clear days from the higher passes.
Trail facts
- Trail area
- Calenzana to Conca, Haute-Corse and Corse-du-Sud
- Best season
- June 15–October 1
What to bring
- Technical hiking boots (ankle support mandatory)
- Trekking poles strongly recommended
- Emergency bivouac or sleeping bag
- 3+ litres water capacity
- Map (IGN Top 25, 4149OT and 4253OT)
- Waterproof jacket and warm layer even in summer
- Headtorch
Location
Northern start: Calenzana, 20214 Calenzana. Southern end: Conca, 20135 Conca
42.5080, 8.8520 View on map
Highlights
- Traverses the full mountainous spine of Corsica across 15–16 stages covering 180 km
- Reaches Bocca Minuta at 2,225 m, the trail's highest point above sculpted granite ridges
- Mid-route CFC railway stop at Vizzavona enables staged or bail-out logistics
- PNRC refuges provide food, dormitory beds, and campsite pitches along the entire route
- Views across the Tyrrhenian Sea to the Italian mainland on clear summit days
Tips for visiting
- Book PNRC refuges online at parc-naturel-corse.com at least 6–8 weeks ahead for July and August — pitches sell out quickly.
- Allow an extra rest day at Vizzavona or Corte at the mid-route; legs typically feel the accumulated ascent by stage 7 or 8.
- Carry a printed or offline IGN map (sheets 4149OT and 4253OT); phone signal is absent on most high-altitude sections.
- Start each stage before 08:00 to clear exposed ridgelines before afternoon thunderstorms build, typically from early afternoon.
- Trekking poles reduce knee strain significantly on relentless descents — bring them even if unfamiliar with the habit.
- The CFC train allows hikers to join or exit at Vizzavona mid-route, making a north-only or south-only GR20 feasible.
When to visit
Late June to mid-September offers snow-free passes and operational refuges; early July weekdays are quieter than August weekends. Avoid starting in late May or early June when the northern high passes may still carry snow and ice.
Accessibility
The GR20 is entirely unsuitable for wheelchair or stroller access. The trail crosses technical alpine terrain including boulder scrambles, steep scree, fixed chains, and high-altitude passes. Even sections near road access points involve rough, rocky paths that require full mobility and strong hiking fitness.
Frequently asked questions
Do hikers need a permit to walk the GR20?
No hiking permit is required to walk the GR20 trail itself. However, overnight accommodation at PNRC-managed refuges requires advance reservation, and camping outside designated zones within the Parc Naturel Régional de Corse is prohibited.
Is it possible to walk only part of the GR20?
Yes — the CFC train stop at Vizzavona at the mid-point is the most common split, allowing the northern or southern half to be completed independently. Individual stages can also be accessed by car at various col car parks, though access roads are often narrow and seasonal.
What is the best time of year to walk the GR20?
Mid-June to early September offers the most reliable snow-free conditions on the high passes. Late June and September are preferred by experienced hikers for fewer crowds and cooler temperatures; July and August see the highest footfall and warmest weather, making exposed ridges very hot midday.
How fit do hikers need to be for the GR20?
The GR20 requires excellent cardiovascular fitness and prior multi-day hiking experience. The average stage involves 800–1,200 m of ascent on rocky terrain. First-time long-distance walkers are strongly advised to attempt a gentler route such as the Mare e Monti or a single southern GR20 stage before committing to the full route.
Are there food resupply points along the route?
Refuges along the GR20 sell basic provisions — pasta, tinned food, energy bars, and limited fresh supplies — at a premium. Main resupply towns are Vizzavona (mid-route, accessible by train) and Bavella near stage 14. Hikers carrying tents typically carry 2–3 days of food between resupply points.