Las Hoyas

Las Hoyas is a Konservat-Lagerstatte, an exceptionally preserved Early Cretaceous fossil locality, near the city of Cuenca in the Province of Cuenca, Castile-La Mancha, Spain, within the La Huerguina Formation, a sequence of lacustrine limestone and marl deposited in a freshwater wetland roughly 125 million years ago during the Barremian stage. The formation is 60 to 100 meters thick and its fossils owe their exceptional preservation to microbial mats, rapid burial and stagnant bottom waters. Las Hoyas is best known for its exquisitely preserved dinosaurs, especially enantiornithine birds, and has also yielded abundant fish, the most common vertebrates at the site, along with crocodylomorphs, the most common amniotes, and fossils spanning numerous other phyla.