OpenInterstate

OpenInterstate publishes open, versioned datasets of the United States interstate highway system, derived from OpenStreetMap.

Getting usable interstate data out of raw OSM means downloading planet-scale files, standing up a spatial database, and untangling how thousands of mappers labeled the same roads. This project does that work once per release and ships the result as plain CSV, so consumers can skip straight to the data.

Get the data

Every release is a dated, checksummed tarball on the releases page:

gh release download --repo tldev/openinterstate --pattern '*.tar.gz'

A release contains seven CSV tables plus GPX reference routes, GeoJSON examples, a manifest, checksums, and source lineage:

Table	Contents
corridors	Contiguous directional interstate corridors
corridor_edges	Graph edges assigned to corridors
corridor_exits	Normalized exits linked to a corridor
exit_aliases	Source exit aliases mapped to normalized exits (currently empty)
places	Reachable places and services
exit_place_links	Spatial proximity links between exits and places
reference_routes	Routes for QA, examples, and exploration

Every table and column is documented in datapackage.json (Data Package standard) and rendered at https://openinterstate.org/schema. Example DuckDB queries live in examples/duckdb.

Scope

Releases cover signed interstates only, including lettered branches such as I-35E and I-69C. OpenInterstate is an upstream data layer: it does not define consumer packaging or application-specific contracts. Drive-time reachability scores are published separately by openinterstate-reachability.

How it works

us-latest.osm.pbf (Geofabrik)
  -> osmium prefilter (interstate-relevant ways, exits, POIs)
  -> osm2pgsql flex import into PostGIS
  -> SQL and Rust derive stages (graph, corridors, exits, routes)
  -> CSV export with manifest, checksums, and lineage

Releases are built by the Release Build GitHub Actions workflow, triggered manually with an opt-in publish step. Pull requests run the same mechanics against a small Rhode Island extract as a smoke test.

Build it yourself

Docker is the only requirement:

./bin/openinterstate --data-parent /path/to/openinterstate-data build

This downloads the source PBF, starts PostGIS, imports and derives, and writes a release under a workspace keyed by the source file's SHA-256. Re-runs skip stages whose inputs have not changed. Add --release-dir <path> to collect release artifacts in one place.

Repository layout

• bin/ local command-line entrypoint
• compose.yaml Docker services for PostGIS and the build runner
• docker/runner/ tool image with Rust, osm2pgsql, osmium, and Python
• schema/ bootstrap SQL, derive SQL, and the osm2pgsql flex mapping
• crates/ Rust builders for the graph, corridors, and reference routes
• tooling/ release export and CI scripts
• datapackage.json machine-readable schema for every public table
• schemas/ release manifest schema
• examples/ example consumer queries

Contributing

See CONTRIBUTING.md. Naming, schema, and release-format review are the most useful contributions right now.

License

Code is MIT (LICENSE). Data releases are OpenStreetMap-derived and published under ODbL 1.0 (DATA_LICENSE.md).