Cañón del Atuel

The Atuel cuts through a range of sedimentary rock southwest of San Rafael, and the road that follows it runs for around fifty kilometres between walls eroded into towers, hoods and fins in reds, purples, yellows and greys, each formation given a fanciful name by local guides. Below, the river runs a strong green between dams, and the stretch below the Valle Grande reservoir is used for rafting through the summer on gentle to moderate water, along with kayaking, ziplines and horse riding from bases along the road. The canyon is usually driven from the Valle Grande end toward El Nihuil, or as a loop from San Rafael, with viewpoints and stops throughout.

What you actually see

• The eroded walls - towers and fins of coloured rock along the road.
• The green river - the Atuel running between the dams.
• The rafting sector - the run below the Valle Grande reservoir.
• Valle Grande - the reservoir with beaches and activity bases.

When to go

October to April for rafting and warm weather; midsummer is very hot in the canyon with little shade. Rain can bring rockfall and close sections of the road. Morning and late light give the best colour on the walls.

Honest expectations

Parts of the road are unpaved, dusty and rough, and the loop takes a full day with stops. The formation names are marketing rather than geology. Activity operators cluster near Valle Grande and can be crowded in January, and the river is dam-controlled, so flow varies.

Nearby

San Rafael is the base; El Nihuil and its reservoir lie at the far end.