The attached excel sheet is intended to be used as a finding aid for county records series and the publications of various historical societies in the United Kingdom. This document was created to support the work of Professor Margo Todd, her students, and the University of Pennsylvania’s Department of History. The information provided in this document is based on series holdings in the University of Pennsylvania libraries, primarily Van Pelt‐Dietrich, as well as those held in storage at LIBRA. It is designed to give a quick reference to these holdings, where they are located, and which geographic region they cover. It is by no means exhaustive and is a work in progress, but it should give the reader a good idea of the holdings available to the UPenn community.