A team of US and Bolivian researchers has revealed that the Carreras Pampa archaeological dig site in Bolivia’s Torotoro National Park is the single largest dinosaur track site ever discovered.How many individual prints have to be at the site to nab to make that kind of claim? Try 18,000 individual prints preserved across what used to be the muddy shoreline of a shadow freshwater lake about 70 million years ago.According to research published in PLOS One, nearly all the tracks belong to theropods, the bipedal carnivorous dinosaurs that are cousins of today’s birds. The site boasts an absurd 16,600 three-toed prints, plus almost 1,400 “swim tracks,” where dinos apparently kicked along the lake bottom like giant dogs. The prints range from dainty 10-centimeter foot taps to massive 30-centimeter stomps. Most came from small to mid-sized theropods roughly human-height, pacing along the shore in both directions like commuters during rush hour.Scientists Just Discovered the World’s Largest Dinosaur Track Site in BoliviaWhat makes Carreras Pampa legendary isn’t just the number of tracks but what preserved them all in place. The lakebed was a Goldilocks zone of soft-but-sturdy carbonate-rich mud filled with tiny calcium carbonate grains and ostracod shells. That sediment created the perfect firmness for dinosaurs to leave detailed, long-lasting impressions. Once covered by fresh sediment, those footprints were locked in place for millions of years, as sturdy and resilient as our modern-day cement sidewalks.The site was such a perfect spot for capturing imprints that it captured more than just footprints. Any part of a dinosaur that touched the ground left a permanent mark. Claw drags and tail trails can be found throughout as well.Researchers identified 11 types of tracks in total, some of which were so well preserved and so vividly detailed that they could identify the kind of action the dinosaur was performing when it left that mark. For instance, the researchers found evidence of a dinosaur making a sharp turn as it walked along the sediment.Torotoro is now one of the best places on earth to catch a glimpse into dinosaur behavior, and all it took to provide us with this look into the ancient past wasn’t some fanciful sci-fi tech. All it took was the right kind of mud.The post World’s Largest Dinosaur Tracks Site Found in Bolivia appeared first on VICE.