The Institute proves a report as well as mapping of congestion in urban areas (Congestion Data for Your City).

BTS geodata portal

The CTPP data product, based on American Community Survey (ACS) data, is designed to help transportation analysts and planners understand where people are commuting to and from, and how they get there. The information is organized by where workers live, where they work, and by the flow between those places.

(US Census Bureau; county, MSA, and State level data; Approximately 10 years ago to current)
Select a table, then customize by geography and other variables.

The National Transportation Atlas Database is a set of nationwide geographic databases of transportation facilities, transportation networks, and associated infrastructure. These datasets include spatial information for transportation modal networks and intermodal terminals, as well as the related attribute information for these features.

Historic railroad .shp and .kml files that were created as a part of a project on visualizing railroad history.

The TIGER/Line files are a digital database of geographic features, such as roads, railroads, rivers, census statistical boundaries, etc. covering the entire United States. The data base contains information about these features such as their location in latitude and longitude, the name, the type of feature, address ranges for most streets, the geographic relationship to other features, and other related information. They are the public product created from the Census Bureau's TIGER database. TIGER files can be used as a detailed detailed street source and for geocoding.