Irazu volcano crater and lake

This is a closer view peering down into the lake inside one of the five craters of Irazu Volcano. The plant growing in the foreground is called a "poor man's umbrella," as its leaves are huge. In contrast to the lush vegetation in most of Costa Rica, only a few species of plants grow in the moonscape of the high volcanic craters.

There are many fumaroles in the national park, frequent emissions of clouds of steam, and frequent seismic activity at this active volcano.