Not many countries in the world can boast such evidence of these colossal ancient creatures. Some 68 million-year-old dinosaur tracks were discovered in southern Bolivia around Sucro only by the end of the 20th century, in 1994. One can find 6 to 8 different types of footprints, forming up to 5,000 unique tracks across Cal Orcko limestone rocks, commonly referred to as the "dinosaur wall." The longest track winds 347 meters and is attributed to the baby dinosaur scientists named "Johnny Walker." The footprints are rare traces of the Cretaceous period which can now be observed year-round, but best during the dry season from May to October.