Conical Volcán Arenal is the youngest stratovolcano inCosta Rica and one of its most active. The 1670-m-highandesitic volcano towers above the eastern shores of LakeArenal, which has been enlarged by a hydroelectricproject. Arenal lies along a volcanic chain that hasmigrated to the NW from the late-Pleistocene Los Perdidoslava domes through the Pleistocene-to-Holocene Chatovolcano, which contains a 500-m-wide, lake-filled summitcrater. The earliest known eruptions of Arenal took placeabout 7000 years ago, and it was active concurrently withCerro Chato until the activity of Chato ended about 3500years ago. Growth of Arenal has been characterized byperiodic major explosive eruptions at several-hundred-year intervals and periods of lava effusion that armorthe cone. Arenal's most recent eruptive period began with a major explosive eruption in 1968. Continuousexplosive activity accompanied by slow lava effusion and the occasional emission of pyroclastic flows hasoccurred since then from vents at the summit and on the upper western flank. (Global Volcanism Program)ArenalLocation: 10.463° N, 84.7003° WElevation: 1.657 m HOME