Just in Case! – Parque Nacional Volcan Poás, Alajuela Province, Costa Rica

Although the last major eruption was in 1910, visitors can still see geysers explode into the air up to 820 ft (250 m) high. Chances of getting wet are pretty remote as the crater descends almost 1,000 ft (300 m) and is one of the largest active volcanoes in the world. Standing on the rim, visitors often smell the sulfur in the air, which at times has proven to be acidic enough for the park to close. It is from this crater that the effects of acid rain can be seen on the vegetation surrounding the landscape. Around the huge main-crater is the beautifully blue-green colored Botos Lake (Laguna Botos) and on the opposite side, the von Frantzius cone.

Poás was near the epicenter of a 6.1-magnitude earthquake in January 2009 that killed at least forty people and affected Fraijanes, Vara Blanca, Cinchona (the most affected area), the capital San José, and the Central Valley region of Costa Rica. There was also eruptive activity in 2009 involving minor phreatic eruptions and landslides within the northern active crater. Poás eruptions often include geyser-like ejections of crater-lake water.

On February 25, 2014, a webcam from the Volcanological and Seismological Observatory of Costa Rica (OVSICORI) captured the moment a dark cloud exploded about 1,000 feet in the air from a massive crater of the Poás Volcano. This volcano remains active today