Conical Volcán Arenal is the youngest stratovolcano in Costa Rica and one of its most active. The 1670-m-high andesitic volcano towers above the eastern shores of Lake Arenal, which has been enlarged by a hydroelectric project. Arenal lies along a volcanic chain that has migrated to the NW from the late-Pleistocene Los Perdidos lava domes through the Pleistocene-to-Holocene Chato volcano, which contains a 500-m-wide, lake-filled summit crater. The earliest known eruptions of Arenal took place about 7000 years ago, and it was active concurrently with Cerro Chato until the activity of Chato ended about 3500 years ago. Growth of Arenal has been characterized by periodic major explosive eruptions at several-hundred-year intervals and periods of lava effusion that armor the cone. Arenal's most recent eruptive period began with a major explosive eruption in 1968. Continuous explosive activity accompanied by slow lava effusion and the occasional emission of pyroclastic flows has occurred since then from vents at the summit and on the upper western flank.
Hanging Bridge hike in the rainforest
Tempted by the innocent looking low bridge, they march on into the rainforest
Howler monkeys
Our guide, Manny, shows us some of the moss growing in the rainforest near Arenal
Hanging bridge time
In the rainforest
Photo stop
Ants, hard at work
Clouds obscure the peak of Arenal
Aaron, Debbie, Mike, Olu, Richie and Shannon
Rainbow over Lake Arenal
Almost totally clear
Steam from Arenal
and then it dawns on us that the volcano is active...
...but active is good. Releases pressure. We feel better now.