Poás Volcano National Park Costa Rica (Volcán Poás)

The story of conservation at Poás began in Tennessee's Great Smoky Mountains National Park in the 1960's. Mario Boza was a student when he visited the park in the United States and was so impressed that he developed a plan to manage the area around Poás Volcano in a similar way, presented it as his masters thesis, and pursued its implementation. How the plan was adopted as an integral part of the birth and development of the National Park system in Costa Rica is described in David Rains Wallace's book, The Quetzal and the Macaw.

Poás Volcano rising out of the clouds as seen from the north (© R. Krueger-Koplin)

Cacho Negro Volcano rising out of the clouds blocks the view of Poás from the north
(photo © R. Krueger-Koplin)

Attractions and Amenities

Poás volcano is a powerful symbol of the geothermal forces that formed Costa Rica.

When the mist and clouds part you'll see the sulfuric, bubbling, green rain fed lake at the bottom, surrounded by smoke and steam rising from fumaroles. Water from the lake is constantly seeping through cracks in the hot rock, evaporating and building pockets of steam. When the pressure in these pockets exceeds the weight of the water above, the steam breaks through in geysers that rocket up to 820 feet (250 meters) high. Don't worry about getting a shower though, the crater is 1,050 feet (320 meters) deep. At almost a mile (1.6 km) across it's also the largest active crater in the world.

Sulfuric lake at the bottom of Poás Crater from the viewing area
(photo © T. Harari)

Poás is active, but don't expect to see a full fledged eruption or even any lava flow here, the most recent period of eruptive activity ended in 1954. The last major activity was in 1910 when nearly a million tons of ash was ejected along with an immense column of smoke and steam.

A modern visitors center (wheelchair accessible) and small museum explains and interprets the geothermal and ecological attractions in the park. A cafe serves coffee and hot drinks—as much to wrap your hands around to warm them as anything else—sandwiches, and snacks.

The volcano provides an excellent if extreme example of the effects of acid rain. Around the caldera, and for several miles downwind, the vegetation is stunted brown and black by the tainted moisture that precipitates from the omnipresent clouds near the peak.

Trails that lead through cloud forest stunted and twisted, not only by volcanic emissions but the rigors of the cold windy high altitude habitat. Lake Botos fills an extinct crater at the end of one trail, and is home to many cloud forest birds including hummingbirds, tanagers, flycatchers, toucanets, Costa Rica's national bird the clay-colored robin, and the area's most famous avian resident, the resplendent quetzal.

In the region:
Poás Volcano National Park is an easy day trip from most locations in the central valley, and can easily be combined with a number of other activities.

A tour of a coffee farm is the perfect way to drive the chill out of your bones after an early morning atop Poás.

The lower slopes of Poás Volcano are covered with fruit farms and huge ornamental flower farms. Most of the roses, lilies and other flowers grown in this region are driven to Juan Santamaría airport in the central valley then shipped air-express to Miami where they are put on planes headed to all parts of the United States and Canada. You have probably seen some of them at your local florist.
We stopped in at the processing station of one of these farms where they were happy to give us a spontaneous tour. You'll rarely see more flowers in one spot.

Although we don't know of any organized tours to do this, Poás is a great downhill ride. Hire a taxi or throw your bicycles on the bus to the park. Get an early start, see the park in the morning then spend the afternoon coasting down all or part of the 4,900 feet (1,500 meters) to the central valley.

When to visit:
The best time to see into the crater at Poás Volcano National Park is in the morning, in the dry season—from January to April. Clouds build starting in the late morning and obscure the views into the crater, over the northern lowlands, and into the central valley as you travel to and from the park. Because of its proximity to San José, the park is popular with Ticos, particularly on weekends so if you have a choice, visit midweek.

If it is clear, use sunscreen. At this elevation, this near the equator, the sun's rays are intense and you can get a sever burn in an hour or less. If it's not clear, don't forget your sweater and windbreaker. Even at midday it can be nearly freezing at this elevation, and the wind whips around the crater.

Volcanoes
by Mauro Rosi (Editor), Paolo Papale, Luca Lupi, Marco Stoppato, Franco Barberi (Editor), Jay Hyams (Editor), Paperback, 335 pages, Publisher: Firefly Books, (March 2003), ISBN: 1552976831

not yet reviewed
Written by experts in the field and beautifully illustrated. The first section covers the science and the second the details of over 100 active volcanoes around the world.
Buy from Amazon $US 17.47 -or-
Barnes&Nobel member price $US 24.95

Encyclopedia of Volcanoes
by Haraldur Sigurdsson, Bruce Houghton, Hazel Rymer, John Stix, and Steve McNutt, Hardcover, 1456 pages, Publisher: Academic Press, (October 1999), ISBN: 012643140X

not yet reviewed
Complete coverage of every aspect of volcanoes in a beautiful and accessible form.
Buy from Amazon $US 99.95 -or-
Barnes&Nobel $US 99.95

Volcano information on the Web
Scientific site in Spanish tracking the activity of the volcanoes of Costa Rica