These maps, based on research by the San Francisco Estuary Institute’s Center for Resilient Landscapes, reconstruct California ecosystems as they were in the late 18 th and early 19 th centuries, and compare them to present-day landscapes. They are designed to provide an understanding of the complexity and diversity of California ecosystems, to help explain how landscapes worked, to track persistence and change, and to identify potential future scenarios. The changes made evident when the maps are compared remind us of the enormous power we have to shape the landscapes we inhabit, and of the wide range of potential options available—options to create diverse, functional, and beautiful landscapes, inspired by the past and grounded in local potential—as we imagine and then create the future.