How did the rapid spread of the railroad and telegraph in the late 19th century remake American life, economy, and policies? With the advent of the telegraph, communication over great distances became instantaneous. At the same time, railroads brought about rapid movements in people and goods. These technologies were not merely contemporaneous but deeply intertwined. Scholarly research on the implications of these twin technological transformations has hitherto been limited by an inability to examine when and where people gained access to these new networks, and the nature of that access. To address this gap, this project produced a digital map of railroad stations and telegraph offices in the United States during the late 19th and early 20th centuries. This map covered annual changes over a 30- to 40-year span of time in which these networks expanded to cover North America. Information for the map came from recently digitized books that include tables from telegraph and railroad trade publications. Interdisciplinary collaboration enabled the team of scholars to compile and transcribe a large set of archival records and images, and unify work on communication infrastructure. The team also created a website to crowd-source the transcription and geographic placement of railroad stations and telegraph offices. The data and maps generated through this process will be shared with researchers and the general public in the forms of interactive maps as well as downloadable data via a new website dedicated to the project.