Chaoyang is known as China’s “fossil city”. It is located in the Liaoning Province in northeast China, approximately a four-hour train ride from Beijing. During the 1990’s many new and unique fossils were discovered in this region. Some of the finds completely revolutionized the palaeontology community’s ideas of dinosaurs and shed new light on the origin of birds. It was the discovery of feathered dinosaur fossils that caused all the excitement. The fossils have been dated to 124 million years ago from the lower Cretaceous period. At that time there was a shallow lake in the area that was buried under layers of mud and volcanic ash which preserved the skeletons of many creatures in tact. The fine shale formations created by the ash even preserved the traces of their feathers. The Sihetun Geopark Fossil Site is where the feathered dinosaur fossils were first discovered within the thin layers of shale.