The East Riding of Yorkshire, including the Holderness coastline, is known for its rapidly eroding boulder clay cliffs, which contain a mix of reworked Jurassic and Cretaceous material. This constant erosion regularly exposes a variety of fossils, meaning finds can be unpredictable.
Fossils can be collected along much of the coastline, with Mappleton being one of the most popular and accessible locations. Material found here may include ammonites, belemnites, and other fossils derived from the underlying strata.
Further north at Danes Dyke, near Flamborough Head, the Cretaceous chalk is particularly rich in fossils, especially well-preserved sponges, making it an important site for collectors.