As you might have guessed from the dinosaur figure in the plaza or the dinosaur head sticking out of city hall, Torotoro has become synonymous with paleontology. The village, which sits in a wide section of a 20km-long valley at an elevation of 2600m, is flanked by enormous, inclined mudstone rock formations bearing bipedal and quadrupedal dinosaur tracks from the Cretaceous period (spanning 145 million to 65 million years ago).
There are numerous tracks (huellas) all over the place and much work remains to be done on their interpretation. Many different dinosaur species are represented, both herbivorous and carnivorous.
The closest tracks are at Cerro Huayllas, at the entrance to the village, on the other side of the river. It's behind a locked fence so you'll need an official guide to enter (most people visit as part of the hike to Cañon de Torotoro & El Vergel). Above the water but below the road are the area’s largest tracks, made by an enormous quadruped dinosaur (diplodocus or similar) and measuring 35cm wide, 50cm long and 20cm deep. Near here, just above the road, the angled plane of rock reveals a multitude of different tracks, including a long set from a heavy quadrupedal dinosaur that some have posited are those of the armadillo-like ankylosaurus.
Along the route to Umajalanta cave, the flat area known as the Carreras Pampa site has several excellent sets of footprints (on both sides of the path). These were made by three-toed bipedal dinosaurs, both herbivores (with rounded toes) and carnivores (pointed toes, sometimes with the claw visible).
All the tracks in the Torotoro area were made in soft mud, which then solidified into mudstone. They were later lifted and tilted by tectonic forces. For that reason, many of the tracks appear to lead uphill. Many local guides, however, incorrectly believe that the footprints were made in lava as the dinosaurs fled a volcanic eruption.