Arenal Volcano

Location: Within Arenal Volcano National Park, 17 kilometers west of La Fortuna, north of  the Tilaran mountain range

Altitude: 5358 feet (1633 meters) above sea level

Arenal Volcano is one of Costa Rica's most popular attractions, and for good reason. On clear nights lava flows can be spectacular, especially when viewed while soaking in a naturally-heated hot spring at one of the nearby thermal resorts.

Volcano aficionados have declared Arenal the third most perfect volcanic cone in the world. It is also the youngest and most active volcano in Costa Rica, and one of the ten most active volcanoes in the world. Arenal is a stratovolcano, similar to Japan's Mt. Fuji. 

Arenal Volcano has had several names throughout the years, including Arenal Peak, Rio Frio Volcano and Pan de Azucar (Sugar Loaf). Pre-1968, locals regularly climbed the densely-forested peak which had only one crater with fumarole activity.

The volcano was silent for more than 400 years until suddenly, in 1968, it erupted with such force that it blew off the whole western side of the mountain, creating three new craters. The villages of Pueblo Nuevo, Tabacon and San Luis were destroyed in the eruption which claimed 78 lives.

Arenal has been consistently active since 1968 and now has small, daily eruptions (known as strombolian activity), with major eruptions less frequently. Explosions shoot ash plumes more than one kilometer above the volcano and send boulders the size of houses down the slopes.

Lava flows tend to change directions every six to eight months, and typically favor the southwest and/or northwest slopes of the volcano. There are many hotels and lodges in the La Fortuna area catering to the awesome view, which is best observed on a clear night.  The Chato Volcano is Arenal's neighbor to the southeast, also located within Arenal National Park.

Volcanologists in Costa Rica constantly monitor Arenal's activity and warn that the volcano could have a major eruption in the future. The biggest threats are pyroclastic flows, a mixture of hot rocks and gases that can travel up to 80 kilometers per hour, destroying everything in their path. Arenal Volcano National Park officials mandate that tourists stay on marked paths and keep a good distance from the crater.