Partway along the Arequipa–Cotahuasi Canyon route, the road branches off for Andagua, a small village at the head of the Valley of the Volcanoes. The small valley, sandwiched between Colca and Cotahuasi and only 65 kilometers long, is a seemingly endless lava field, lorded over by the snow-capped Coropuna and Escribano and punctuated by more than 80 perfect volcanic cones.

In the middle of it all is a lake and the gentle Río Andagua, which runs underground through much of the valley. Few people travel here, and those who trek along this valley need to carry a tremendous amount of water.

Near the village of Ayo, a few days’ trek away from Andagua, the valley leads to Lago Mamacocha. There is also an adventurous five-day route, which retraces the 1929 route of Shippee and Johnson and passes through Chacas to Cabanaconde in Colca Canyon. Andagua-bound buses leave several times a week from Arequipa’s bus station.

For those with a four-wheel-drive vehicle, a fascinating circuit connects Cotahuasi and Andagua and then heads to the Colca Canyon via Cailloma. Except in Chivay, there is probably no gasoline along this route and not even the best maps are completely accurate, but the scenery is legendary.