Located three kilometers from the town center of Cornago. The quality and quantity of fossil tracks make this one of the most visited sites, aided, no doubt, for its easy access. The replicas of the site that were displayed in different exhibits throughout Spain played their part in contributing to its popularity.
However, in spite of their beauty and excellent state of preservation, these are not tracks in the strict sense of the word. Technically, they are what the experts call "carbon copies": the mud which preserved the imprint is not the layer that the dinosaur directly stepped on, but rather the stratum below it, which was still soft . In addition to the dinosaur prints here, it is worth noting that fossil tracks of other animals, like small birds and turtles, have been found here.
Five large fossil track sites can be visited at Los Cayos:
- Los Cayos “A”: This site covers a substantial areas of some 1,200 square meters. The 425 fossil tracks can be seen clearly. Thirty six of them form trails and there are a significant number of separate tracks. The bigger fossil tracks (measuring 45 centimeters long) were made by large theropods.
- Los Cayos “B”: This site is located 300 meters below the previous site and the fossil tracks are grouped into two big groups or levels. There are 230 fossil tracks grouped in 450 square feet area, 69 of them trails of theropods. Fossil tracks of various sized theropods can be viewed on the other group or level and, although the majority of them are separate, five trails have been catalogued.
- Los Cayos “C”: These small fossil tracks are found 200 meters from the previous site. Fifteen tracks of dinosaurs and 58 smaller fossil tracks have been catalogued there. A group of separate tracks that appear to belong to a small bird can be found eight meters away.
- Los Cayos “D”: A large number of dinosaur tracks are found at this site, 200 meters away from Los Cayos C. The tracks are big, but badly eroded and were made by ornithopods.
- Los Cayos “E”: This tiny site to the north of Los Cayos B has a surface area of only four square meters. Nine fossil tracks made by small theropods can be seen here
Near the fossil tracks, there are many fossils of turtles, crocodiles, shellfish and vegetation from the Cretaceous.
