Blue lake cave in Brazil is one of the most beautiful and most famous lakes in the world. The amazing fact is that no human set foot inside the magnificent cave lake. This lake was founded in 1924 when an Indian discovered it. This cave is really deep, and inside it, divers discovered lots of mammal fossils, and bones, which belong to the Saber-tooth tiger. Water in this lake is really clear and the human eye can see the bottom of the lake down to 295 feet. This is something amazing.