Cachi is the town at the top of the Calchaquí Valley, 160 kilometres north of Cafayate and 2,280 metres up, with the snow-capped Nevado de Cachi filling the skyline behind it. It is a small colonial town of whitewashed adobe around a shaded plaza, and it is the natural overnight stop on the best road trip in northern Argentina.
On the plaza stands the church of San José, whose ceiling, pews and confessionals are made of cardón cactus wood — the ribbed, hollow trunk of the giant cactus that grows all over these hills. Beside it, the archaeological museum holds the region's pre-Hispanic finds and is worth an hour.
The road north from Cafayate runs through a string of small towns — San Carlos, Angastaco, Molinos, Seclantás — each with its adobe church, and through the Quebrada de las Flechas, a canyon of tilted sandstone blades. From Cachi the route drops back to Salta over the Cuesta del Obispo, crossing the Parque Nacional Los Cardones, a plateau forested with giant cactus.
Most people do the loop Salta–Cafayate–Cachi–Salta in two or three days and sleep in Cachi on the way round. Parts of Ruta 40 on the valley stretch are unpaved and slow, so allow more time than the distance suggests.