Until 2010 Arenal was Costa Rica’s most active volcano. In recent times it has entered a period of quiescence, although you can still hear subterranean rumbles and see the odd ash column. The surrounding national park contains a bizarre landscape of solidified lava flows, lush forest and tropical flora and fauna.
- Where: Alajuela Province
- Ideal for viewing: boa constrictor, mantled howler monkey, violet sabrewing, agouti, armadillo