Digital Collections The Auraria Library Digital Collections (ALDC) serves as the holistic digital repository for the three schools that make up Auraria Campus, as well as the Auraria Higher Education Center (AHEC) and Auraria Library itself. The ALDC encompasses various collections of digitized historical and scholarly materials ranging from faculty journal articles to the rich and robust collections of Auraria Library Special Collections. Historical photographs, manuscript collections, rare books, and audiovisual material all make up the myriad collections of the ALDC and will always be free to use for all visitors.