The adventure and excitement you’ll enjoy in today’s Arenal was 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.
Arenal Volcano Travel Guide
At 5,437 feet (1,657 meters), 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.
The adventure and excitement you’ll enjoy in today’s Arenal was 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 many more amazing things to do during your visit to Arenal.
How to start planning your Arenal Visit?
Visit the Arenal Volcano National Park
La Fortuna village scenery, hotels, dining, and nightlife
Lounge in hot springs heated by the volcano
Hike and swim the 200-ft waterfall hike near town
Largest lake in Costa Rica is here Lake Arenal
Discover 100 things to do around Arenal
Navigate the rocky terrain and enjoy volcano views
Ask the local experts!
Video: Arenal Volcano
Get a glimpse of the volcano with local expert & guide Hector.
How the Arenal Volcano Volcano Works
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.
Plate tectonics is the theory that Earth’s outer layer is made up of plates, which have continued to move throughout Earth’s storied history. The theory explains the dynamics of mountain formation, earthquakes and volcanoes. It also explains how similar animals came to live on what are now widely separated continents.
You probably wouldn’t recognize the Earth if you could see it 225 million years ago. At that time, all of the major continents formed a giant supercontinent, called Pangaea. Around 200 million years ago, Pangaea began to rift and split apart. A buildup of heat underneath Pangea may have initiated this splitting. The ocean filled areas between the new sub-continents and the landmasses continued to move apart, riding on separate plates, until they reached the positions that they occupy today. The continents are, in fact, still on the move.
What drives plate tectonics is not precisely known. One theory is that convection within the Earth’s mantle pushes the plates in much the same way that air, heated by your body, rises up and gets deflected by the ceiling. Another theory proposes that gravity pulls the colder and heavier ocean floor with more force than it pulls t
Read More: What is the history of Arenal Volcano?