• Tagged Abismo Anhumas, adventure, Blue Lake Cave, Blue Lake Grotto, Brazil, caving, environment, Gruta do Lago Azul, nature

Bonito is the heart of eco-tourism in Brazil because it is famous for its natural beauty, prehistoric caves, waterfalls, and clear blue waters. One of the most beautiful is Blue Lake Cave (Gruta do Lago Azul). Amazingly, it is believed that no human set foot inside the cavern with the cobalt blue waters until 1924 when an Indian from the Terena tribe discovered it. That’s not to say nothing ventured down into the 328 feet (100 meters) deep cave, since massive mammals fossils from about 10,000 years ago were discovered by cave divers, bones such as those belonging to the Saber-tooth tiger and giant ground sloth. Because the water is so clear, it is hard to fathom that Blue Lake Cave is about 295 feet (90 meters) deep. Adventurers start with a hike through the forest, then go caving through a wide entrance that allows sunlight to illuminate the gorgeous blue waters as well as stalactites and stalagmites of all different sizes. Here’s a look at Bonito, Mato Grosso do Sul, Brazil and some of the extraordinary and unusual ecotourism adventures and true natural treasures including beautiful Blue Lake Cave. [25 Photos]

• Tagged adventure, cave, cavers, caving, exploration, extreme sports, Hang Son Doong, karst, Phong Nha Cave, Phong Nha-Kẻ Bảng, Phong Nha-Ke Bang National Park, Phong Nha–Kẻ Bàng karst, Son Doong Cave, stalactites, stalagmites, Thien Duong Cave, Tien Son Cave, Vietnam

Hidden in the thick tropical forest of Vietnam is a land of phenomenal caves. Phong Nha-Ke Bang National Park contains the oldest major karst area in Asia; the karst is believed to have formed 400 million years ago, during the Palaeozoic era, With every cave discovery, that cave is considered the largest and longest in Phong Nha-Ke Bang, only to learn later that yet another even more massive cave has been found. This national park is home to the largest cave in the world and is said to be the home of the many of the world’s most beautiful caves. It’s famous for its cave and grotto systems, about 300 caves and grottos, of which only 20 have been surveyed by Vietnamese and British scientists. UNESCO named it a World Heritage Site for its geological values. Spectacular stalactites and stalagmites create an underground fairy-tale-like world where formations look like the caves possess jagged teeth or home to strangely alien trees. Visitors to Phong Nha-Ke Bang National Park most often visit the massive Paradise Cave and huge Phong Nha Cave as seen below. If you don’t expect to ever travel to Vietnam, then here is a virtual trip to see the mysterious and massive world hidden beneath Phong Nha-Ke Bang National Park . [39 Photos, 2 Videos]