From OpenStreetMap Wiki
401 section from 416 to Kingston southwest-bound mapped Oct 28th, 2006. Looks like a good start.
- both directions from about Toronto Airport west to About London done.
- Interchanges from about Toronto Airport west to Guelph are half-done. To complete these interchanges, take the exits from 401 southbound on the crossing road, then continue in the same direction on 401. Once each for EB and WB required.
- 401 / 410 interchange needs attention.
- 401 / 407 interchange needs attention. (Video toll road)
- Toronto East to Highway 115, both directions done. Interchanges and overpasses need work!
- 401 coverage extends to Belleville on both carriageways.