Acamarachi, Volcanic peak in Atacama Region, Chile

Acamarachi is a volcano in the Atacama Region of Chile that rises 6,046 meters above sea level with a symmetrical shape. Its steep upper flanks and a lava dome on its northern side define the distinctive appearance of this mountain.

The mountain was first climbed in 1939 by Italian mountaineers, marking an important moment in the modern exploration history of this remote region. This early expedition opened the way for further research and scientific observations of the volcano.

The summit's four ceremonial platforms are laid out in a cloverleaf arrangement, an Inca sanctuary among at least fifteen known in the Andes. Figurines found there include a silver female figure and a Spondylus-shell figure wearing a yellow miniature tunic of camelid wool with multicoloured decoration, in the Catarpe style.

The first recorded ascent was made on 19 February 1939 by Aldo Bonacossa and Remigio Gerard, members of an Italian expedition to the Puna de Atacama. The volcano lies about 80 km southeast of San Pedro de Atacama, and the summit crater sits at roughly 5,950 m, so acclimatisation and a guided group are needed.

The summit crater of the mountain holds a small lake that remains in liquid form due to underlying geothermal heat. This unusual feature reveals the continued volcanic activity beneath what appears to be a dormant surface.