National Park General Information   Size: 12,060 hectares Distance from San José : kilometers . Trails: Yes. Dry Season: January through March.

Arenal Volcano National Park

The most characteristic feature of this national park is the impressive and majestic Arenal Volcano, an almost perfect active cone 1,633 meters high, whose regular eruptions offer one of the most extraordinary and awe inspiring natural sights in Costa Rica. The four most important types of vegetation in the park are the perennial wet and very wet forests that cover about 47% of the area. There's also cloud forest and riverine woodlands, where several endemic species can be found, like the brunelia costaricensis and the epiphytic pineapple.

Thirty-five species of fish, 135 species of reptiles that include tortoises, snakes and lizards, and 131 known species of mammals can be found here. An amazing 53% of the species that make up the national bird population are also found here making this park and the surrounding area a birdwatcher's paradise.

Undisputedly one of Costa Rica 's foremost tourist attractions, the active Arenal Volcano is the centerpiece of this relatively new national park, created in October,1994. In addition to protecting what is currently one of the world's most active volcanoes, the area now under park service management encompasses the watersheds of several rivers and streams that flow into Lake Arenal , the country's most important source of hydroelectric power.

The imposing Arenal Volcano rises in nearly perfect conical form out of the western end of the San Carlos plains. Its periodic eruptions of ash and molten rock, accompanied by thundering sonic blasts, are an unforgettable experience anytime, but become extremely spectacular after dark. When the light of day has dimmed, the glowing red igneous rocks ejected with each eruption trace fiery arches in the night sky before crashing down on the steep slopes and finally extinguishing themselves.

Columns of lava also push their way down the sides of the volcano and pieces of the advancing sections continually break off under the weight of new flows bearing down from above. At night, these falling pieces are visible as chunks of rolling red rocks, adding to the natural fireworks display between the frequent eruptions.

From the 600-meter elevation where visitors are allowed to approach a hardened lava flow from the 1968 eruption, Arenal rises another 1,000 meters to its 1,633-meter summit, and although the peak is still three kilometers away, it is definitely "in your face!"

There is little vegetation or wildlife to be seen in the immediate area of the main viewing site, since the effects of the major devastating eruption of 1968 are only slowly being overcome. Nevertheless, this area offers a unique opportunity to witness the early stages of lava flow colonization by a handful of plant species adapted to the task. Farther away, there are forested areas which escaped direct damage and provide better wildlife viewing, however, as of yet the park service does not maintain any well-marked trails in these areas, which include the Volcano Chato Volcano to the southeast of Arenal.

To get there: Arenal National Park is most quickly reached from San José by taking the Inter-American Highway west to the town of San Ramón and the road north through Angeles, La Tigra and Chachagua to La Fortuna. Driving west out of La Fortuna , the road takes you 180 degrees around the volcano to the park ranger station. There is public bus service from both San José and Ciudad Quesada to La Fortuna.

An alternative and equally scenic route for those coming from Guanacaste, is to take the Inter-American Highway to the town of Cañas and then drive up into the hills to the town of Tilarán and follow Lake Arenal around its northern shore to the base of the volcano.

Climate: Being under the influence of Caribbean slope weather patterns, Arenal Volcano receives anywhere from 3.5 to 5 meters of rain per year. Even when it isn't raining, clouds often gather around the volcano's peak, obliterating a full view of the mountain. At lower elevations within the park (i.e., the viewing area at the volcano's western base), the temperatures are warm during the day, but can get chilly at night, especially if there is a breeze.

History: The settlers that colonized this region in the early part of the 20th century referred to Arenal Volcano as "the mountain" and apparently, despite its conical shape, did not realize it for what it is. Thus, when the quiescent volcano exploded on July 29, 1968, producing a cloud of hot volcanic gases and covering several square kilometers with lava, some 87 people living in the areas of Tabacón and Pueblo Nuevo lost their lives.

Since this tragic eruption (the first following at least 300 years of inactivity, according to some geologists), Arenal has remained active, but fortunately at a level posing little threat to visitors.