Roughly the size of West Virginia, Costa Rica possesses an astounding number of volcanic formations – 112 to be exact! In fact, what were once thought to be potholes are actually extinct craters! Well, not really, but don’t fear, only seven of these volcanoes are considered to be active.
Volcanic activity in Costa Rica is the result of friction between the Cocos and Caribbean tectonic plates. This friction partially melts rocks, which are then pushed to the surface by the pressure of the earth’s crust. This molten magma then rises to the earth’s surface to escape through cracks and fissures.
Between 1723 and the present day, Costa Rica has experienced powerful eruptions by the Rincón de la Vieja, Arenal, Poás, Irazú and Turrialba volcanoes. The most serious eruption was that of Irazú volcano in 1963. It erupted spewing clouds of smoke and ash that hovered over San José and Cartago for two years. Over 100 square kilometers of the surrounding countryside were devastated. On August 24th, 2000, Arenal Volcano was the scene of Costa Rica’s most recent volcanic eruption.
The highest of Costa Rica’s volcanoes is Irazú, the most active is Arenal, and Poás has the second widest crater in the world. Most are within a few hours drive from San José, Costa Rica’s capital city. If you are planning on visiting Costa Rica, make sure to visit at least one of these fiery wonders. Below are some of the most well known of Costa Rica’s many volcanoes.
Located at the foot of the Tilarán Mountain Range and next to scenic Lake Arenal, the conical Arenal Volcano is the youngest stratovolcano (where many layers of volcanic material accumulate over the course of intensive activity) in Costa Rica and one of its most active. Considered extinct until its thunderous eruption in July of 1968, the 5,500 ft. volcano has remained active ever since and is one of Costa Rica’s main tourist attractions. If the weather is clear, incandescent lava ejected from the crater and rolling down the slopes can be seen at night.
Location: Arenal Volcano National Park is located on the northern edge of the Tilarán range, at the east end of Lake Arenal. 55 miles (88 km) north west of San José (90 miles, 145 km by road). Nearest town La Fortuna.
Located within Braulio Carillo National Park, the Barva Volcano is the only one of the Central Valley’s four volcanoes that has not erupted since colonial times. The volcano is located 13 miles north of San José and rises to a height of 9,500 feet above sea level. The volcano is easily identifiable by its three volcanic promontories known as Cerro Las Tres Marías (Three Marys Hill). The climb to the summit of the volcano is fairly popular among hikers and provides panoramic views of the Central Valley and rural countryside. Use the park entrance via San José de la Montaña. From the road, foot trails go to the summit of the volcano.
Location: 13 miles (21 km) Northeast of San José.
Costa Rica’s highest volcano and one of its most active, rises to 11,260 ft. immediately east of the capital city of San Jose. Its name is derived from the indigenous word Istarú, which means “hill of earthquakes and thunder”. Near the crater, a large moonscape of steep hills and enormous accumulations of volcanic ash are interspersed with stunted mountain vegetation. The main crater measures more than half a mile across and is almost a thousand feet deep. The first well-documented historical eruption occurred in 1723, and frequent explosive eruptions have occurred since. Ashfall from its last major eruption during 1963-65 caused significant disruption to San Jose and surrounding areas. Irazú was established as a protected area in 1955, and forms part of the Central Volcanic Cordillera Conservation Area.
Location: Irazú volcano is 15 miles (24 km) east of San José, 34 miles (54 km) by road.
Founded in 1971, the 16,000-acre Poás Volcano National Park forms part of the Central Volcanic Cordillera Conservation Area. The volcano rises almost 9,000 ft. above sea level and is located 20 miles north of the city of Alajuela. It is one of the oldest and most visited parks in Costa Rica.
The most visible and recently formed features at Poás are its irregular, sub conical main crater, which measures 4,265 ft. across and almost a thousand feet deep. The southernmost of two summit crater lakes, Botos, is cold and clear, and last erupted about 7,500 years ago. A lush cloud forest of oak and cypress surrounds the lake, while forests in the Caribbean region of the park tend to be taller and very humid, with many palms, tree ferns and epiphytes.
There have been three major periods of recorded activity, from 1888 to 1895, 1903 to 1912, and 1952 to 1954. The largest recorded eruption took place on January 26, 1910, when an enormous column of smoke and ash rose to a height of 25,000 feet.
Location: 19 miles (30 km) northwest of San José (25 miles, 41 km, 70-90 minutes, depending on the route).
Rincón de la Vieja
Boasting nine craters, Rincón de la Vieja is the largest volcano in northwest Costa Rica. Its varied altitudes and unique position astride the continental divide also make it one of Costa Rica’s most biologically diverse. Rising to 6,000 ft. above sea level, the volcano’s ellipse shaped main crater is over 1,500 feet wide and 300 feet deep. To the east of the crater there is a lake, waterfalls, bubbling sulfuric mud holes and fumaroles. The fumaroles hiss like kettles spitting up odiferous steam and thick gases. The last important eruptions took place between 1966-1970 and were accompanied by clouds of ash, earthquakes and tremors. The Rincón de la Vieja area was declared a national park in 1973, and forms part of the Guanacaste Conservation Area.
Location: 75 miles (120 km) northwest of San José.
Rising to a height of almost 11,000 feet, the Turrialba Volcano sits on the eastern most flank of the Cordillera Central and is actually part of the Irazú massif. According to legend, the name of the volcano was coined by Spanish settlers, who named it Torre Alba, or “white tower”. Vegetation is characterized by tough, twisted branches and small trees. The summit has three craters, of which the middle one is the largest. The west crater exhibits a great deal of heat and gas activity, while the east crater has been inactive for more than a century. Volcanologists estimate that Turrialba has experienced at least six major eruptions in the past 3,500 years. And although the last significant eruption occurred in 1866, scientists believe that it is only a matter of time before another eruption occurs.
Location: 19km (12 miles) northeast of Turrialba.