Guatemala's wild jungle interior is filled with adventure. Guided hikes wind through tropical flora and end up at crystalline waterfalls. There are more than 400 species of birds—including toucans and parrots—in this rain forest expanse, as well as a number of amphibians, reptiles and other animals. However, while bird-watching is a snap, spying other critters may be more of a challenge due to the dense foliage. The big draw, of course, is the falls, with cool pools that are perfect for a refreshing dip post-trek.