Originally Posted by mhnadel

There is a direct bus to Tyson's from Crystal City. I think it's the #23. I've never taken it but I see it all the time. You could get to Crystal City by blue or yellow line from King Street (adjacent to the Alexandria Amtrak station) or directly on the VRE.

As for alternative driving routes, the Fairfax County Parkway isn't helpful since the section that goes through to 66 doesn't start until Springfield or so, which means that you have to do the crawl through Woodbridge and thereabouts, which is where the heaviest traffic is. 123 is a viable alternative, though is only one lane in each direction part of the way. It also has the advantage of actually taking you to Tyson's, rather than a several miles west. (And the disadvantage of possible traffic jams in downtown Fairfax and inevitable traffic jams in downtown Vienna.)