Arenal Volcano has been active for about 7,000 years. This doesn't mean huge explosions happen every day, but a slow trickle of magma can be seen most days. The volcano erupts 22 times per day, on average. The last major eruption was in 2000; the area surrounding the volcano was evacuated.
Arenal is a stratovolcano, built from numerous eruptions over time and composed of layers of ash, lava and rock. These kinds of volcanoes are typically symmetrically formed, like Mount Fuji in Japan. The shape and size of Arenal is attributed to fairly systematic major eruptions occurring at 700-year intervals. The volcano is 5,437 feet tall.
There are dozens of hotels located around the volcano, all at a safe distance. There are even hiking trails up to the lower parts of the volcano and signs indicate when it is no longer safe to hike. The volcano is part of Arenal Volcano National Park, which is also home to Lake Arenal and features a wide variety of wildlife, including birds and small mammals.
