The University of North Carolina at Chapel Hill University Libraries recently kicked off a project to migrate over 5,000 hand-encoded finding aids and other archival information from a variety of mostly homegrown systems to ArchivesSpace. To prepare the data for ingest, we focused recent efforts on mapping locations data for our physical materials to container information in our finding aids. This proved less than straightforward for a variety of reasons, not limited to legacy data formatting, multiple file formats, different interpretations of container hierarchy, and flat file limitations. This poster will detail the steps taken to map semi-controlled locations data stored in a Microsoft Access database and an Excel spreadsheet to finding aid container data in XML format using Microsoft ActiveX Data Objects (ADO) and the Ruby Roo and Nokogiri gems.