In 1840 he published the first official List of Historic Monuments in France, with 934 entries. By 1848 the number had grown to 2,800. He organized a systematic review to prioritize restoration projects, and established a network of correspondents in each region who kept an eye on the projects, made new discoveries, and signaled any vandalism. Though he was a confirmed atheist, many of the buildings he protected and restored were churches, which he treated as works of art and shrines of national history. He often disputed with local church authorities, insisting that more recent architectural modifications be removed, and the buildings restored to their original appearance. He also confronted local governments who wanted to demolish or convert old structures. With the authority of the royal government behind him, he was able prevent the city of Dijon from turning the medieval Palace of Estates into an office building, and he stopped the city of Avignon from demolishing the medieval ramparts along the Rhône River to make way for railroad tracks.