Arenal Volcano Overview
At 5,437 feet, the Arenal Volcano looms large and ominous over the pastured green hillsides that surround its base. Although currently in a resting phase, Arenal remained the country’s most active volcano for the past 43 years. Its storied history is charged with eruptions – both major and minor – that have intimately affected the region and the people who live here.
Formed some 7,000 years ago from the adjacent (and now extinct) Chato Volcano, Arenal’s most recent eruptive period began in 1968 with an explosion that buried three small villages and left 87 people dead. Up until July 2010, the eruptions had been constant, though much less severe—there were effusions of smoke and lava on an almost daily basis.
Since 2010, however, the volcano’s seismicity, explosions and lava flows have decreased significantly. It is, scientists assure us, still alive; it’s just sleeping. At present, visitors will be unable to see lava flowing down its sides or find plumes of ash rising from its top. Still, there is much to see and do here – including rainforest hikes, whitewater rafting, horseback riding and more – while on you Costa Rica Vacation.
Arenal is what is known as a stratovolcano – a tall, symmetrical volcano that’s built upon successive layers of rock, ash and lava. Due to the convergence of oceanic and continental tectonic plates, magma (the molten or partially molten rock that forms beneath earth’s surface) rises into Arenal’s volcanic chamber and can eventually erupt from its top.
1968 saw the largest recorded eruption in Arenal’s history. After nearly 400 years of inactivity, the Arenal Volcano burst open and buried over 5 mi² (15 km²) in rocks, lava and ash.
The Arenal Volcano was consistently active for the past 43 years; smoke, gas and lava would come pouring out its top and down its sides in a spectacular display of geologic activity. This page will introduce you to some of the biggest and baddest eruptions in recent history.
Thanks to geothermal activity beneath Arenal, the area surrounding the volcano is home to a number of hot springs. There are springs for every budget and style, and many serve up unobstructed views of the volcano.
Although it’s one of the more famous volcanoes in Costa Rica, Arenal is not the only one. In fact, the country hosts six active volcanoes and sixty dormant or extinct volcanoes within its borders.
The 29,692-acre (12,016-ha) Arenal Volcano National Park protects both the Arenal Volcano and the dormant Chato Volcano. The park begins near Lake Arenal and has both hiking trails and observational points for visitors to enjoy.
In many ways, Lake Arenal is just as monumental as the volcano that rises above its eastern shoreline. With a surface of over 33 sq mi (85 sq km) and a depth of some 200 ft (60 m), it is Costa Rica’s largest landlocked body of water. As such, it provides ample opportunities for activities such as windsurfing, fishing, boating and more.
Visitors to Arenal can enjoy canopy tours and canyoneering adventures, guided hiking trips or white-water rafting excursions. There are hanging bridges to be explored and hot springs to be soaked in. This page introduces travelers to the most exciting, educational, and relaxing tours in Arenal.
Arenal’s beauty is no secret – countless travelers have told tales of its smoking volcano, vibrant rainforests and monumental lake. These images will help you picture some of the better and lesser-known faces of Arenal.