Orosí Volcano is part of the Orosí‑Cacao volcanic complex and is approximately 500,000 years old, with its last activity around 10,000 years ago. This 50 km² stratovolcano has a well‑developed cone deeply eroded by time and a southwest crater measuring 1 km in diameter. Petrographically, its lavas consist of andesites, basaltic andesites, and olivine‑bearing basalts.
