If you're not sure which roads, The AA have a free online route planner which also does European roads with maps:
http://www.theaa.com/travelwatch/pla...jsp?database=E Might be worth a look with the above in mind.
Can't recommend buying a Michelin map enough though. In fact, I've got a spare if you'd like to borrow it. Just u2u me an address and I'll stick it in the post.