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Costa Rica’s amazing volcanoes

If you’ve read some of our earlier blog posts about Costa Rica, you’ll know that it’s one of the most biodiverse countries on the planet. Despite taking up only 0.03% of the Earth’s surface, Costa Rica contains a whopping 6% of the world’s biodiversity (including sloths and hummingbirds), and this is partly due to its volcanic past.

Arenal Volcano, from a distance
Classic volcano shape – photo: Jennifer Morrow

Home to over 200 volcanic formations, Costa Rica is the most volcanically active place in the western hemisphere. This is because of its location directly above the Ring of Fire – a 40,000km stretch of volcanic activity bordering the Pacific Ocean.

Costa Rica sits right above the point where the Pacific tectonic plate is moving under the Caribbean tectonic plate, triggering hundreds of seismic and volcanic events every year. So what exactly does all this volcanic activity have to do with the biodiversity of Costa Rica?

Irazú volcano Costa Rica
A Costa Rican volcano (biodiversity not pictured) – photo: Philippe Guillaume

Over thousands of years, volcanic eruptions have brought up minerals from deep within the Earth, scattering them across the land as they fall as ash from the sky. These minerals are replenished by the ash after every volcanic eruption, leaving the soil extremely fertile. The more fertile the soil, the more vegetation it can support – and more vegetation means more animals!

Poás volcano, Costa Rica
Poás volcano. Big leaves. – photo: dconvertini

Costa Rica has a volcano to suit everyone. The photogenic Arenal Volcano used to be the country’s most active with over 40 eruptions a day! Since 2010 the volcano has been slumbering, however it’s still a must-visit due to its natural hot springs and various outdoor activities.

Arenal volcano Costa Rica
Arenal volcano, sleeping – photo: Justin Jensen

Irazú Volcano, sitting at 3,432m, is the highest active volcano in Costa Rica with its name deriving from an indigenous word that translates as “mountain of rumbling and trembling”. Irazú is home to five crater lakes, one of which can turn from emerald green all the way to crimson red depending on the mineral concentration in the lake that day.

Irazu volcano, Costa Rica
Irazú volcano, rumbling and trembling – photo: wiredtourist.com

Poás Volcano is popular for the varied landscapes encountered on your way to the summit. At the edge of its caldera, a platform gives stunning views into an inviting turquoise lake – don’t be fooled though, this lake is highly acidic with a pH of almost zero!

A lake on Poas volcano, Costa Rica
Turquoise lake (no swimming) – photo: Carlos Reusser Monsalvez

So whatever volcano you choose to visit – just remember not to stray too far from the beaten path, and to sort out your travel insurance before you go.