Costa Rican Volcanoes

Volcán Irazú is situated just outside of San José, the capital city. It erupted several times during the 20th century. A green, acid lake currently occupies the main crater. For scale, several people can be seen along the fence line in the foreground.

The best way to access the Turrialba summit is on horseback. The Volcán Turrialba Lodge, where we stayed, had plenty of horses for everyone. Even those who have never ridden enjoyed the ascent and really appreciated the descent at the end of the day.

The valleys surrounding Turrialba frequently experience a daily tropical rainstorm well below the summit  giving the feeling of riding on top of the clouds.

Teetering on the Turrialba rim trail is a heady experience. The vertical drop-off into the crater is not an experience anyone wants to try. The outer slope is scaleable on foot but is typically loose material that slows the ascent.

Volcán Turrialba is the sister volcano to Irazú. It has not erupted since colonial time. Recently, however, there have been deep seismic rumblings that have received attention from the local media. The summit is composed of three craters, shown in this image. The farthest is the oldest and the closest is the youngest. Continuous fumarolic emmissions rise from the crater and deposit condensate minerals around the vents. The trail in the middle distance leads to the central crater from which a few minor fumaroles are active. It is too treacherous to enter the active crater but a trail around the rim allows viewing from three sides. On a really clear day both the Atlantic and Pacific coasts can be seen from the summit area.

The bottom of Turrialba's central crater is inactive except for minor steam fumaroles. This allows close inspection of the fumarolic minerals. The descent into the crater is fairly easy, even with the thin air at the summit region (Foto by Liz Mockbee).

Arenal is Costa Rica's most active volcano. Located near the town of Fortuna, it has been in continuous eruption for decades. Eruptive activity is best seen at night.

Tabacon Hot Springs resort provides elegant hot springs recreation. The water that feeds the spring is heated by the magma beneath nearby Arenal volcano. Eruptions are often visible from the springs at night.

One of the other amenities at Tabacon is the in-pool refreshment bar. This is good reason to save Costa Rican change so that paper money doesn't get wet.

Poás is another multicratered cone. Its summit is often enveloped in clouds. The active crater has an acid lake and a lot of fumarolic activity. Phreatic explosions occasionally occur as well as rarer pyroclastic activity. The crater is situated in one of Costa Rica's most modern national parks.

A short distance from the main crater is Lago Bodos, a cold water lake found in an older crater. The water appears to be very fresh; no fumarolic activity is seen here.


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