Aysgarth Falls is a dramatic landmark at any time of year. It comprises a gorge through which the River Ure descends by a series of stepped waterfalls consisting of horizontal layers of hard limestone separated by thin bands of soft shale. These rocks are part of the Yoredale geological series that were laid down on the sea floor over 300 million years ago, while the falls themselves are a product of the Ice Age. The River Ure is clean and rich in wildlife, home to the rare white-clawed crayfish. There is also a rich variety of insect life including mayflies and stoneflies. On a warm summer evening brown trout may be seen in the quieter sections of the river jumping into the air to swallow flies. Several bird species also frequent the river. The dark brown dipper with its white breast may be seen 'bobbing' at the water's edge or diving under the water for food. Pied and Grey wagtails can also be seen here. The site is protected as part of the Aysgarth Site of Special Scientific Interest (SSSI).