The Kessel Run was one of the most heavily used smuggling routes in the Galactic Empire. Han Solo claimed that his Millennium Falcon "made the Kessel Run in less than twelve parsecs". A parsec was a unit of distance, not time. Solo was not referring directly to his ship's speed when he made this claim. Instead, he was referring to the shorter route he was able to travel by skirting the nearby Maw black hole cluster, thus making the run in under the standard distance.

...at least according to Wookieepidia.

I'd like to see that too!