Irazú volcano is located  northeast of the city of Cartago, about  from . It has an extension of  and altitude is about  above sea level.

The Irazú is an active volcano with an extended history of eruptions and erupting cycles, it is also an area of extreme hydrological importance. Several rivers that feed the Chirripó, Reventazón, Sarapiquí and Grande de Tárcoles basins come out of the Irazú volcano.

The name Irazú comes from aboriginal town that lived next to the volcano called Iztarú which means earthquake and thunder cliff. However throughout the years the name was modified to Irazú

It possesses five craters, the most important because their activity are the main crater, almost completely circular with leaned walls which is about of diameter and 300mts deep. The second most important is Diego de crater which has of diameter and deep. Other craters we can find are Playa Hermosa, , and Piroclástico.