The route at a glance
The drive runs one way from San Rafael to El Nihuil, roughly 70 km, and is normally done as a half-day to full-day round trip. The stops below are in driving order, which is the most efficient way to see everything.
- San Rafael (0 km) — fuel, supplies, rental cars, tourist information.
- Canyon entrance / start of RP173 (~25 km) — the road turns into curves and gradients.
- Valle Grande Reservoir (~40 km) — first reservoir and the classic viewpoint.
- El Laberinto rock labyrinth (~45 km) — park and walk among the red pillars.
- Lago Atuel shoreline (~55 km) — the busiest stretch for water activities.
- El Nihuil village (~70 km) — upstream reservoir, food, camping, supplies.
- Volcán Overo turn-off (~80 km) — dirt road to the volcanic cone.
Road conditions and what to expect
RP173 is a paved provincial road for the main canyon stretch, but it is a mountain road: constant curves, gradients and some cliff-edge sections with no barrier on the outer side.
- Speed is limited by geometry more than by the surface — expect a slow, twisting drive.
- Cliff-edge sections get noticeable crosswinds in strong wind; keep both hands on the wheel.
- Rockfall is possible after rain, particularly where the road runs directly under the rock walls.
- Dirt detours such as the Volcán Overo approach need a high-clearance vehicle.
- The road is a public provincial route and generally open, but sections can close temporarily after heavy rain or rockfall — check San Rafael Turismo for the current road status before you travel.
Practical checks before you set off
- Fuel: stations are concentrated in San Rafael city and essentially absent along the canyon — fill up before you enter.
- Signal: mobile coverage is unreliable inside the canyon. Download offline maps and tell someone your plan and expected return.
- Water and food: bring your own. Services are limited until El Nihuil village.
- Sun and wind: there is very little shade, and the canyon is exposed to strong wind most of the year.
- Parking: viewpoint bays are small and fill up on peak-season mornings. Never stop on a curve or an emergency lane.
Timing your drive around the light
The canyon is a photography destination and the light matters. Side-light in the early morning and late afternoon is what brings out the rock strata, while midday flattens everything and is also the hottest, most exposed part of the day.
- Early morning: best light on Valle Grande and the east-facing walls, fewest other cars.
- Late afternoon: warm light on the red rock; good for the return leg.
- Midday: avoid if you can — harsh light, no shade and peak heat in summer.
Combining RP173 with a side trip
Los Reyunos Reservoir is reached from a different direction than the canyon road, so treat it as a separate half day rather than trying to fold it into an RP173 day. The Volcán Overo detour, by contrast, sits at the El Nihuil end and can be added on the way back.
Frequently asked questions
The canyon stretch from San Rafael to El Nihuil is roughly 70 km. Because it is a twisting mountain road with viewpoint stops, allow a half day for the drive itself and a full day if you add a water activity or the Volcán Overo detour.
The main canyon stretch of RP173 is paved. The side roads to places such as the Volcán Overo are mostly dirt and their condition changes with the season, so confirm access locally before setting out.
It is not recommended. The road has continuous curves and cliff-edge sections with limited lighting and unreliable mobile signal, so plan to be back in San Rafael before dark.
No — an ordinary car handles the paved RP173 route and the main viewpoints. You only need a high-clearance vehicle if you plan the dirt detours, such as the approach to the Volcán Overo.