The irazu volcano is a complex volcanic shield. It is the highest active volcano in Costa Rica, and has an area of . It has an irregular subconic shape, and temperatures at its summit vary between , with a record low of −3 °C(26.6 °F) and a record high of 23.2 °C(73.4 °F). Irazu volcano is a stratovolcano with a summit elevation of . Its five craters are easily differentiated. The most important ones, because of their activity, are The Main Crater and the Diego de la Haya crater. The Main Crater is almost circular, has very inclined walls and it measures in diameter and deep. The Diego de la Haya crater is in diameter and deep. Other craters are Playa Hermosa, La Laguna, and El Piroclastico.