CMAP publishes 383 open datasets for United States. Browse them live in Vizzie and turn any one into a map or chart.
CMAP is the open-data portal for United States, covering Illinois. It runs on ArcGIS Hub, Esri's open-data platform for geographic data. You can browse it directly at datahub.cmap.illinois.gov.
On CMAP, a majority of datasets here declare no licence at all. It's important to know that "no licence declared" is not the same as public-domain or free-to-use. Undeclared data carries no explicit permission to copy, adapt, or redistribute it — so reusers should treat it cautiously and check with the publisher before relying on it. Vizzie flags each dataset's licence (or its absence) so you can see this before you build.