Private Tour.You needn’t go far at Arenal Observatory to feel nature’s magic – it’s all around you! And with so many things to do here at Arenal area, you will have a Costa Rica rainforest adventure to remember forever.Here, on our 870-acre property uniquely located right between Arenal Volcano and Lake Arenal, you can explore rainforest, waterfalls, streams, 11 kilometers (7 miles) of trails, and see an amazing wealth of wildlife. Arenal Observatory is a renowned destination for bird watching in Costa Rica, with more than 500 species of birds noted so far in our forest. Nature rises early in Costa Rica. It is worth it to get early in the mourning to see the howler monkeys and birds that were your alarm clock in the morning.