Geospatial data created for the public good is increasingly valuable across academic, economic, and public service domains. Over the last few decades, somewhat of a ‘digital dark age’ has transpired due to the lack of preservation and stewardship of information representing our digital cartographic heritage. Even when datasets have not been lost, the costs to recover them can be significant. From a public service standpoint, archived spatial data enhances citizen access to community information, provides critical resources for urban planning and disaster response, and supports the efficient delivery of essential public services including utilities, transportation, and healthcare. This presentation will describe efforts being undertaken by libraries across the United States to archive geospatial assets with the goal of building momentum across the community, with open source software playing an increasingly vital role in making this preservation both accessible and discoverable. The technical considerations of formal archiving include maintaining data integrity, ensuring interoperability between different systems and agencies, and maintaining metadata about data sources and collection methods. We will discuss a variety of open source solutions currently implemented to guarantee that these valuable resources remain accessible and useful for both current needs and future generations. Some of these solutions include open source digital preservation repositories, serverless infrastructures, metadata catalogs, and common programming tools such as GDAL/OGR and Python. We hope that this presentation will serve as a launching point for communication among data producers, domain specialists, and cartographic practitioners, about how to develop long-term partnerships and strategies for archiving essential geospatial resources.