Arenal Volcano National Park

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Arenal is one of the world's most regularly active volcanoes. Since its famous eruption in 1968 that wiped out a small town, Arenal's frequent explosions send red-hot lava rocks tumbling down the volcano's steep slopes, day and night. If you are lucky enough to visit on a clear night, which is not always the norm-- you'll see to the top- it is 5, 271 feet hight and the night sky turned red by lava spewing from Arenal's crater, at   In the past few years, the forests to the south of the volcano have been declared Arenal National Park, which will likely stretch to meet Monteverde Biological Cloud Forest Reserve.