One of the largest Maya cities in the Americas, Tikal comprises thousands of limestone buildings: palaces, temples, pyramids and sports complexes. Many visitors don’t realize, however, that the main plaza of Tikal boasts an active altar where today’s Mayas still burn copal incense, light candles and make flower offerings to their ancestors, Dr. Hansen says.

The site also serves as a critical habitat for an array of wildlife, including 300 species of birds and several species of anteaters. “You could spend a whole month just looking at the sheer variety of caterpillars,” says Dr. Hansen. “This is truly one of the last patches of pristine rain forest.”

He recommends spending a night at one of the hotels inside or just outside the park and exploring Tikal in the early morning — when animals are most active and day-trippers are still asleep.