See What Remains Beneath Costa Rica's Arenal Volcano

Arenal had been quiet for more than 400 years before the morning of July 29, 1968, when it erupted without warning, killing 87 people and destroying the villages of Tabacon, Pueblo Nuevo, and San Luis. What followed was 42 years of near-continuous activity, transforming a farming region into one of the most visited natural landmarks in Central America.

Arenal Volcano National Park, whose official page covers current trail and access conditions, now protects the volcano and the surrounding forest that has spent over a decade recovering since the last significant activity in 2010. The Volcanological and Seismological Observatory of Costa Rica continues to monitor the volcano closely, since a return to activity, while currently unlikely, remains possible.

The Volcano That Defined a Region

Before 1968, Arenal was simply a hill to the farmers who lived around it, its volcanic origins largely forgotten after centuries of dormancy. The 1968 eruption changed that permanently, and the decades of activity that followed turned the region around La Fortuna from a quiet agricultural town into a tourism hub built almost entirely around the volcano's presence. The town itself grew substantially during those active decades, drawing visitors who came specifically to watch incandescent lava fountains lighting up the night sky.

That transformation shaped the whole area, from hotel development to the hot springs that still draw on the same geothermal system responsible for the eruption itself. Travelers extending their stay often pair Arenal with a trip up to nearby Monteverde's cloud forest, a short but winding drive away that offers an entirely different volcanic and ecological story.

What Happened After the Eruptions Quieted

Arenal's activity declined gradually through the 2000s, with the last significant lava extrusion recorded in late 2010. Since then, the volcano has remained in what volcanologists describe as a resting phase, showing only minor fumarolic activity and no signs of renewed eruption. That decline followed a recognizable pattern, with shorter, less frequent lava flows and a gradual reduction in seismic energy over several years rather than a sudden stop.

That quiet has not meant abandonment. Scientists continue to treat Arenal as an active research site, studying everything from slope stability to how quickly forest recovers on land that was bare rock only a few decades ago, work that has broader implications for understanding volcanic recovery elsewhere in the world.

Walking Across Old Lava Flows

Trails through the park's older lava fields lead directly across rock formed during the 1968 eruption and the decades that followed, some sections still bare enough to show the texture of the flow that created them. Signage along these trails explains the eruption's timeline, giving visitors context for the landscape they are walking through rather than presenting it as scenery alone. Walking the same ground where lava once moved, now cooled and slowly returning to forest, changes how the whole park feels compared to a trail with no history attached.

Our guide to an Arenal volcano hiking adventure covers these lava field trails in more detail, including which sections offer the clearest views of the cone itself.

Forest Returning to Volcanic Ground

Plant life has moved back onto Arenal's older lava flows in visible stages, from lichen and moss on the oldest rock to young trees establishing root systems in accumulated soil. Sections closer to the 1968 flow show the least recovery, while areas affected earlier in the volcano's active period display forest well on its way to resembling the surrounding rainforest. Pioneer species tend to establish first in cracks and pockets where wind-blown soil and organic material collect, slowly building the conditions later, larger trees need to take root.

That gradient offers a rare, compressed timeline of ecological succession, with different stages of recovery visible within a single park depending on which decade's lava a trail happens to cross.

Wildlife Around Arenal Today

Wildlife has returned to the park's recovering forest alongside the plant life, with coatis, howler and white-faced capuchin monkeys, and a wide range of birds now common along trails that were bare rock within living memory. Sloths appear regularly in the forest sections bordering the older lava fields, drawn by the same cecropia trees found throughout Costa Rica's lowland forest. The speed of that return has surprised even researchers who study volcanic recovery elsewhere, since Arenal's tropical climate accelerates both plant regrowth and the wildlife that depends on it compared to recovery timelines seen at volcanoes in cooler regions.

Our packing guide covers what to bring for Costa Rica's climate, worth reviewing for the binoculars and layers that make the most of a full day exploring both the lava fields and the forest sections around them.

Waiting for the Cloud to Lift

Arenal's nearly perfect cone draws clouds and mist more reliably than almost any other landmark in Costa Rica, and a clear, unobstructed view is never guaranteed on any single visit. Mornings tend to offer the best odds, before afternoon humidity builds into the cloud cover that regularly wraps the summit by midday. Even a single clear hour is often enough for the photograph most visitors are hoping for, which makes patience more valuable here than any particular time of year.

Travelers hoping for a clear view sometimes find it worth extending a stay by a day specifically for this reason, since even a persistent morning cloud bank can lift unexpectedly given enough patience. Our guide to Costa Rica's volcanoes covers a few backup viewpoints worth checking if Arenal itself stays clouded in.

Stand Beneath Arenal and See What the Lava Left Behind

Arenal's story is not just about the eruption that defined it. It is also about what happens afterward, when a devastated landscape spends decades quietly rebuilding itself into one of the more compelling ecological recovery stories in Costa Rica, one still unfolding season by season for anyone paying close attention.

Gondwana Ecotours builds time at Arenal into the Costa Rica: Secluded Wildlife Adventure with guides who explain both the volcano's history and the ecology now returning to its slopes. Our broader look at ecotourism in Costa Rica covers how recovery stories like this one connect to the country's wider conservation model.

For more details about what is included in our itineraries, please visit our tour pages before booking.

Wildlife sightings and clear volcano views are never guaranteed, but time and patience improve the odds of both. Download our travel details for the most accurate picture of what the Costa Rica: Secluded Wildlife Adventure itinerary actually includes.