Strolling to a Hell Vent: The Poás Volcano

June 18, 2015 — We could smell it before we saw it, that sulfurous stink heavy on the air, like the land itself had gone bad. And it kind of had. We were walking toward a hot pustule on the Earth’s surface known as the Poás Volcano.

The ring of fire cuts an arc through Coast Rica, blistering the country with some 60 or 70 volcanoes, about a half dozen of which are active. Poás is one of the latter. But that’s not why we chose it. Poás was just the most convenient volcano, a phrase I love to death and, according to Google Search, isn’t used enough in the world.

Poás is about 30 miles north of San Jose, and it took us about an hour and a half to get there on San Jose’s notoriously slow roads. From the parking lot and visitor center, though, it was a mere quarter-mile stroll up a paved path to the viewing area. Like I said, a convenient volcano.

Because of the geography of the landscape, we never saw a cone or anything dramatic from afar. We just passed the evacuation instruction signs set up “in case of volcanic activity” and the warnings for those with asthma or hypertension to limit their time there, walked up to the guardrail, and gazed into its massive maw.

Which we couldn’t see.

At first I didn’t understand. We had timed it right, purposefully arriving early to both avoid the large crowds (it’s a convenient volcano) and because at most times of day the volcano is obscured by fog emanating from the surrounding cloud forest. The morning is the best chance to see it.

Turns out, Poás was just saying hello.

I’d been to volcanoes before, Mount St. Helens in Washington and Mount Vesuvius in Italy. Although both are technically active volcanoes, neither was stirring on our visits, the former being all snow-capped and serene and the latter cloud-capped and crowded.

Besides a few rumbles here and there, Poás itself hadn’t done any impressive erupting since the 1950s. But what I at first took to be fog was actually gas and steam spewing from its fumaroles. This thing was putting on a little show. Fortunately, every once in a while the smelly whiteness would abate or the wind would change, and we got a clear view deep into the monster.

The Poás crater is about a mile wide and about a thousand feet deep. In its center is a small lake called Laguna Caliente—Hot Lagoon. It’s extremely acidic, devoid of life, probably tastes good on fries. In photos online, it appears pale green, but on our visit it was colorless, almost shiny, like a pool of mercury. I assume from all the steam reflecting in it. The lake does have a layer of liquid sulfur on its bottom, so don’t dip your fries too deep.

Once we’d had all the sulfur smell we could stomach, we took the long way back to the parking lot through the cloud forest. We saw zero of the much-promised bountiful wildlife along the mile-long loop of trail, but we did see Laguna Botos. Unlike Laguna Caliente, this lake filled an inactive crater and was in an idyllic setting cozied about by the forest, although it was still highly acidic.

Overall, Poás Volcano National Park is a strange combination of easy, pleasant tourism and a great potential for inhospitability, like volcano eruptions and acid rain.

As we left, the cloud forest fog was rolling in, making the visitor center a hazy-looking figment and ensuring that the volcano crater would be invisible to those unlucky enough to mistime their visit. Sometimes Poás is an inconvenient volcano.

But at least they could still smell it.