Hi Tom,
fair enough, here is my Continental Vacation Top Ten (not in any particular order). These are not necessarily the absolute best courses in their respective countries, but certainly top tier and, keeping with the vacation theme, in an area that is generally worth visiting. Also, a discovery process is always part of a great vacation, so I'll go for lesser known courses whenever possible:
Switzerland: Gerre Losone (7)
Why: Plain fun, unassuming, great holiday golf.
In the area: Lago Maggiore, classic courses at Lugano and Ascona
Austria: Millstätter See (8-)
Why: Front 9 defies belief.
In the area: Carinthian Lakes, Alpine lifestyle.
Italy: Acquasanta (8+)
Why: Untouched early Golden Age track with pine trees.
In the area: Rome. Period.
Slovenia: King's Course at Bled (6-)
Why: Do your part to help finance the restoration of a great, classic layout.
In the area: Julian Alps panorama road, Lake Bohinj, Bled.
Czech Republic: Cihelny (7+)
Why: Feels good, very relaxing.
In the area: classic Bohemian spa towns.
Germany: Taunus-Weilrod (7+)
Why: Brace yourself for a full Donald Harradine experience.
In the area: Frankfurt Airport (not a Tourist attraction, but you're gonna be there at some point on your European vacation)
Belgium: Royal Golf Club des Fagnes (7-)
Why: Stately parkland course, well away from the crowded coast.
In the area: The original spa town of, well, Spa. The Haute Fagnes Nature Reserve. More Tom Simpson at Royal Hainaut and Royal Sart-Tilman.
Denmark: Fanø (7+)
Why: Best holiday links ever.
In the area: worthwile courses at Esbjerg and Blåvandshuk.
Sweden: Mölle (7+)
Why: Impress your buddies with this remote cliff-top gem.
In the area: Skåne has an abundance of good golf, including the Falsterbo peninsula.
France: Hardelot Les Pins (8+)
Why: The best French course you can actually play.
In the area: Le Touquet. Kent (if you feel like cheating).