The last time Volcán Irazú awoke was in the first half of the 1960's, when, for four years it showered the residents of Cartago and San José with ash, clogged the air with smoke, and sent glowing boulders rolling down its sides. Today, as you travel along the southern slope of the volcano to the park, the potato, onion, and cabbage fields give way to dairy farms at higher elevations. The next eruption can't be predicted with much accuracy, but currently the only activity in the crater is from fumaroles releasing toxic steam.
Attractions
The summit of Volcán Irazú is near tree-line, and the wind and volcanic activity conspire to give the effect of a moonscape. There are several craters rimmed by gnarled, scorched trees, and lined with brilliantly colored rain fed mineral pools. There are few inhabitants in this harsh environment, but two you should keep an eye out for are the aptly named Volcano Junco and Volcano Hummingbird. There is a small visitors center and displays explaining volcanism (if you are interested in how volcanoes work, there is an extensive visitors center and museum at Poás Volcano National Park)
