In 1992 the Arizona Geological Survey (AZGS) organized a repository in which drill core that the AZGS has accumulated through donations is stored and available for public inspection. The repository is presently located in the basement of the Corbett Building (210 E. 7th Street) in Tucson, Arizona. Core samples in the facility represent almost 300 individual drill holes and approximately 150,000 linear feet of hole. All the core has been skeletonized (either by the donor or by AZGS geologists) to varying degrees, with from 20% to less than 1 % of the original core retained. Fourteen of Arizona's fifteen counties are represented in the storage facility by at least one drill hole, with Apache, Cochise, Maricopa, and Mohave Counties represented by the most individual holes. The core was produced during various projects ranging from geotechnical site assessments to metallic mineral exploration.