About 25 km up the Dadès Gorge, between the village of Aït Arbi and the famous switchbacks, the canyon walls give way to a stretch of bizarre eroded rock pinnacles — slender, fingery columns standing in clusters, formed by millennia of wind and water working on softer rock between harder layers. French-speaking guides call them Doigts de Singes (Monkey Fingers); guidebooks sometimes call them the Brain Rocks.
A small turnout on the right side of the road (heading up the valley) gives the standard photograph. A short, easy walk up among the formations is the only way to appreciate their scale — they are taller than they look from the road, and you can clamber around the bases.
A small kiosk often sells mint tea and fossil souvenirs at the turnout. The rocks make a natural lunch stop on the half-day gorge excursion from Boumalne.