The massive active crater os this 8,884-foot-high volcano regularly emits a plume of noxious steam, and the destruction caused by past eruptions is easy to see, weather permiting. But a short walk through the nearby forest leads to an exctinct crater, filled with the emerald waters of Botos Lake and surrounded by lush forest. Poás is Costa Rica's most popular park and it has an excellent visitor´s center and a nature trail through the cloud forest complete with ecological poetry. A paved road leads right to the summit of Poás, which stands north of Alajuela. You should head there early in the morning during the rainy season.