Visiting French friends nr Reims next weekend for few days then did intend to go south but worried that sites may be a bit full!!so now wondering about going to luxemberg then along the Mosel.got about 9 days then back to Reims.Any suggestions as to must see as not been this direction before.Normally we go to France in May/june but this time "busy Season"Would ideally like to stay in Luxemberg for 1 or 2 nights.