Arenal is the Costa Rican volcano that erupted catastrophically in 1968 after centuries of apparent inactivity.
Arenal’s major eruption began on 29 July 1968 with powerful explosions and pyroclastic flows. Nearby communities, including Pueblo Nuevo and Tabacón, were destroyed, and more than 80 people died. The eruption also created new craters and dramatically changed the volcano’s profile.
Before 1968, Arenal was generally regarded as dormant or inactive, although its exact previous eruptive history remains uncertain. After the 1968 event, it remained one of Costa Rica’s most continuously active and closely monitored volcanoes for decades. Lava flows, explosions, and ash emissions were recurring features.
Arenal is often confused with Poás, Irazú, or Turrialba, all prominent Costa Rican volcanoes. Unlike those volcanoes, Arenal was especially famous for its near-conical shape and persistent activity visible from the surrounding tourist region. Its last major eruptive period ended in 2010.