some of the hills in marin county are pretty brutal from what i hear. not that they're terribly long, or steep, it's just that there's so damn many of them one right after another...a lot of very strong riders had difficulty riding the courses in SF/marin county (the SF race was a crit, and the marin race was more of a distance/technical course with hills and such) this year in whichever big race they had in mid september. i hear lance had a triple. i could've helped out with being a neutral mechanic at both of them if i had gotten off my lazy ass.
anyway, i think they'd definitely have to hit california, and go through the rockies and into like, nebraska for flats...or utah...utah has very nice roads.
however, i think we're dreaming if anyone thinks something like this will actually happen. the U.S. relies too heavily on it's roads and highways for transportation of people and goods. also keep in mind that the US is friggen huge and it can take up to two 8 hour days of driving just to cross a state and a half...having just moved form boston to SF three months ago, and taken numerous bus trips across the country, i know how long it takes to get across. my god there is so much to see and do!!!