Wilberforce Falls on the Hood River in Canada
National Geographic | January 1986
The Remarkable Dinosaur Footprint Wall
Located 3 miles (5 km) from Sucre, Bolivia is Cal Orko, an imposing limestone slab 0.9 miles (1.5 km) long and over 328 feet (100 m) high. On this steep face with an inclination of 72 degrees, visitors can look back in time to when dinosaurs roamed the Earth over 68 million years ago.
At Cal Orko you will find 462 distinct dinosaur tracks from at least 8 different species, totaling an incredible 5,055 dinosaur footprints. So how do thousands of dinosaur footprints come to be, on a seemingly vertical rock face hundreds of feet high? The location used to be the shore of a former lake, that attracted large numbers of dinosaurs.
The creatures’ feet sank into the shoreline in damp weather, leaving marks that were solidified by later periods of drought. Wet weather then returned, sealing the prints below mud and sediment. The wet-dry pattern was repeated several times, preserving multiple layers of prints. Tectonic upheaval then pushed the flat ground up to the brilliant viewing angle that it is today.