Metropolitan Travel Survey Archive
The U.S. Metropolitan Travel Survey Archive is a project to store, preserve, and make publicly available, via the internet, travel surveys conducted by metropolitan areas, states and localities. As of 2007, the archive held 58 surveys comprising 2,718,329 trip records, 516,108 person records, 219,097 household records, 173,354 vehicle records, and 528,847 location records.
Source: Wikipedia — Metropolitan Travel Survey Archive (CC BY-SA 4.0)