The area described in this memoir is an important agricultural region. It includes Ripon and Thirsk, situated in the low-lying, largely drift-covered Vale of York. To the east, the landscape is dominated by Hambleton Hills, and to the south-east by the Howardian Hills. These upland include part of the North Yorkshire Moors National Park. This account should be of interest to amateur and professional geologists and anyone interested in the countryside.