ACA

This is the day the trip climbs onto the roof of the Calchaquí Valleys and doesn't come down. The road from La Poma to San Antonio crosses the Abra del Acay, the highest point on the entire length of Ruta 40, and everything about the day — the pace, the fuel, the lunch — is organised around respecting that climb.

North to Cachi

The 9:00 am departure from Seclantás follows Ruta 40 north along the Río Calchaquí, through Molinos and past the archaeological site of La Paya, before reaching Cachi by mid-morning. Fuel at the ACA station in town — the last easy fill-up before the crossing, and worth taking seriously given what lies ahead. Cachi itself, a national historic site with cobbled streets and adobe architecture, is worth a slow pass through even without stopping to explore properly: the Iglesia San José, completed in 1796 on the main plaza, is notable for interior furnishings carved from cardón cactus wood, a building material distinctive to this valley and rarely seen anywhere else. An artisan market operates alongside the plaza.