The CAÑÓN DEL ATUEL is one of San Rafael’s main attractions, a beautifully wild canyon linking two man-made lakes along the Río Atuel, to the southwest of the town. Visits begin at the reservoir furthest away, the Embalse del Nihuil, reached along the winding RN-144 towards Malargüe, up the Cuesta de los Terneros to the 1300m summit, which offers great views of the valley below; and then via the RP-180, which forks off to the south. The lake lies 92km southwest of San Rafael.

The partly sealed RP-173 then squeezes in a northeasterly direction through a narrow gorge whose cliffs and rocks are striped red, white and yellow, contrasting with the beige of the dust-dry mountainsides. Wind and water have eroded the rocks into weird and often rather suggestive shapes that stimulate the imagination: tour guides attach names like “the Nun” or “the Toad” to the strange formations. The road then passes a couple of dams, attached to power stations, before swinging round the other reservoir, the Embalse Valle Grande. Sticking out of these blue-green waters are more strange rock formations, one of which does indeed look like the submarine its nickname suggests. From the high corniche roads that skirt the lakeside you are treated to some grand views of the waters, dotted with kayaks and other boats, and the mountains beyond. Near here starts the stretch of the Río Atuel used for whitewater rafting. Raffeish, at RP-173 Km35, Valle Grande (t0260 443 6996, wraffeish.com.ar), is the most reliable and ecologically conscious operator, and has an office here. Trips last an hour, along an easy stretch for beginners, or a couple of hours or more, taking in a tougher Grade II section of the river; take a change of clothes, as you get soaked. The scenery along the way is pleasantly pastoral along the more open parts and staggeringly beautiful in the narrower gorges.