When you take the dirt track that leads to Aparzo, northeast of Humahuaca, at the halfway point you come to the Mirador del Hornocal. Located 4 200m above sea level, this lookout offers a fabulous view of the multicoloured mountains of the Sierra del Hornocal (or Cerro de 14 Colores). We would almost advise you to come back at different times of day to see the different colours. It's definitely worth using an agency, as accessing the site by car can be difficult.