Some say this river in northwestern Colombia's Macarena Mountain Range is worthy of being the eighth wonder of the world. Amid a tropical climate, the national park in which it's located is packed with rain forests, dry forest, savannahs, and waterfalls. But its most eye-catching feature is Caño Cristales ("Crystal Channel") , which between July and November turns red, yellow, green, and black thanks to macarenia clavigera, an aquatic plant. Yet another "see it to believe it"!

Read about 14 other spectacular spots in Tripatini member Megan Sashyl's post 15 of the World's Best Lesser Known Travel Wonders.