This volume contains the proceedings of the 16th International Symposium on Spatial and Temporal Databases (SSTD 2019). Included are the research contributions that were presented at SSTD 2019 in Vienna, Austria. The symposium brought together, for three days, researchers, practitioners, and developers for the presentation and discussion of current research on concepts, tools, and techniques related to spatial and temporal databases. SSTD 2019 was the 16th in a series of biannual events. Previous symposia were held in Santa Barbara (1989), Zurich (1991), Singapore (1993), Portland (1995), Berlin (1997), Hong Kong (1999), Los Angeles (2001), Santorini, Greece (2003), Angra dos Reis (2005), Boston (2007), Aalborg (2009), Minneapolis (2011), Munich (2013), Hong Kong (2015), and Arlington (2017).