Travel all the way to Europe just for a scenic drive?
The Best drive I've ever had in my life was Grossglockner-Hauhe Alpenstrasse, Tirols, Austria.
If you want an amazing auto tour, visit the Tirols in late spring/early summer. Rent yourself a good car -- couldn't find a WRX myself, had to settle for a VW GTI -- and drive this world-famous alpine highway. Give yourself at least a week to enjoy the surrounding area, and wait for a crystal clear day (if possible) to drive Grossglockner. The highway is an engineering marvel. Smooth blacktop snaking in and out of butt-puckering alpine cliffs, through tunnels (some of them 15+ miles long!), and scenery unlike anything you have ever seen in your life. When you reach the summit, watch out for black ice and tour busses, but otherwise have at it! The speed limit in Austria seems to be quite a subjective matter - no matter how fast I went, there was always someone passing me!
The road spits you out at the base of the Italian Dolemites. Cross the border, grab some dinner, and take one of the many other scenic routes back into Austria. If you're a driving enthusiast, you will remember it for the rest of your life!
Anyone else know of great international drives?