About Orosi
Orosi is a stratovolcano(es) rising to 1,659 meters (5,443 feet) in Costa Rica's Middle America-Caribbean Volcanic Regions. No historical eruptions have been recorded, though the volcano is classified based on geological evidence of past activity.
Geography & Climate
Orosi is located in Costa Rica, within the Central America Volcanic Arc of the broader Middle America-Caribbean Volcanic Regions. Situated at 10.98° N, 85.47° W in the Northern Hemisphere, the volcano lies within a tropical climate zone. With a summit elevation of 1,659 meters above sea level, Orosi is a moderately sized peak that remains accessible to hikers and researchers for much of the year. The volcanic landform is characterized as a composite, which describes the physical shape and structure of the volcanic edifice as observed from the surface.
Geological Context
Orosi sits in a subduction zone, where one tectonic plate dives beneath another, creating intense heat and pressure that generates magma. Subduction zones are responsible for many of the world's most explosive volcanoes and deadliest eruptions. For communities in Costa Rica near Orosi, this tectonic setting means the volcano is capable of producing powerful explosive eruptions, pyroclastic flows, and lahars that can threaten populated areas within tens of kilometers of the summit. The dominant rock type is andesite / basaltic andesite, a dark, fine-grained volcanic rock that forms from rapidly cooling, low-viscosity lava. Basaltic eruptions tend to be less explosive and produce fluid lava flows that can travel long distances. While less immediately dangerous than explosive eruptions, basaltic lava flows can destroy structures and infrastructure in their path, and volcanic gases released during these eruptions can affect air quality over a wide area.
GVP Reference Summary
Orosí is one of a cluster of four eroded and vegetated cones in the Guanacaste Range at the NW corner of Costa Rica. Volcán Orosí itself has a conical shape as viewed from the north or west, but its flanks are heavily eroded. The complex includes Orosí, Orosilito, Volcán Pedregal, and Cacao. The highest peak of the volcanic complex is 1659-m-high Volcán Cacao, 5.5 km SE of Orosí. The summit of Cacao is cut by two large horseshoe-shaped calderas breached to the SW and east related to edifice collapse. The age of the latest activity of the complex is not known. Historical eruptions were reported from Orosí in 1844 and 1849, but even at the time of the first volcanological observations at the end of the 19th century, Orosí was overgrown with large trees, and the eruptions may actually have been from neighboring Rincón de la Vieja. The latest documented volcanic activity produced mudflows (perhaps secondary) about 3500 years ago.
— Smithsonian Institution, Global Volcanism Program
0 Recorded Eruptions
No eruption records available for Orosi.
Real-Time Data
USGS Alert Level
Thermal Anomalies
Frequently Asked Questions About Orosi
Is Orosi an active volcano?+
Orosi is not currently classified as active. Its activity evidence is listed as "Evidence Uncertain." No recorded eruptions have been documented. However, no volcano is ever considered permanently extinct.
How high is Orosi?+
Orosi has a summit elevation of 1,659 meters (5,443 feet) above sea level. At 1,659 meters, it is a moderately sized volcanic peak, roughly comparable to Mount Vesuvius (1,281m).
What type of volcano is Orosi?+
Orosi is classified as a Stratovolcano(es). Stratovolcano(es) volcanoes have distinct geological characteristics that set them apart from other volcanic types.
Where is Orosi located?+
Orosi is located in Costa Rica, in the Middle America-Caribbean Volcanic Regions. More specifically, it lies within the Central America Volcanic Arc. Its exact coordinates are 10.980° latitude, -85.473° longitude.
Is it safe to visit Orosi?+
Orosi can generally be visited, but as with any volcano, visitors should check local conditions and any advisory notices before traveling. Costa Rica may have specific regulations for accessing volcanic areas. Guided tours are often the safest and most informative way to experience a volcano.
