Transportation improvements in the nineteenth century loom large in the historiography of the profession during the twentieth century. This article describes the ongoing construction of a historical geographic information systems (GIS) transportation database designed to provide new insights into the impact of the transportation and communications revolution in the continental United States by providing evidence on the spatial dimensions of those changes over time. It also reviews some preliminary findings and reinterpretations based upon these data.am taking advantage of the opportunity afforded me by my presidency of the EHA to write what amounts to a personal memoir. It is something of an homage to data for data have been good to me. During my career, I have collected many different data sets; some as a research assistant, others as a principal investigator.