US Interstate Highways

The Dwight D. Eisenhower National System of Interstate and Defense Highways is the largest public works project in history: roughly 48,000 miles of controlled-access highway knitting the continental United States into a single drivable network.

This atlas tracks it the way road-trippers experience it — route by route, state by state. Each segment you mark is real mileage: complete I-90 in Washington and you've banked about 300 miles of the system. Progress here is measured in miles driven, not checkboxes.