Geography is playing an increasingly important role in areas of HCI ranging from social computing to natural user interfaces. At the same time, research in geography has focused more and more on technology-mediated interaction with spatiotemporal phenomena. Despite the growing popularity of this geographic human-computer interaction (GeoHCI) in both fields, there have been few opportunities for GeoHCI knowledge sharing, knowledge creation or community building in either discipline, let alone between them. The goal of this workshop is thus two-fold. First, we will seek to sum up the state of GeoHCI knowledge and address GeoHCI core issues by inviting prominent researchers in the space to share and discuss the most important high-level findings from their work. Second, through our interdisciplinary organizing committee, we will recruit participants from both fields, with the goal of laying the groundwork for a community that works across intra- and interdisciplinary boundaries.