On the popular routes, these are snapped up early. If you're flying internationally, you might want to look into airfare consolidators . Consolidators have contracts with airlines to buy blocks of seats at volume discounts and sell them at reduced rates. You'll get a much better deal booking your rental car from the U.S. before you go. Remember, cars are a lot smaller in most other nations than in the U.S. Be sure to ask about size when you book your car, particularly if you're traveling with a group, or will be toting lots of luggage.
Some countries require international driver's licenses.
Check with your local tourist board or automobile club to learn if your destination does. If you're driving in the U.S., get help plotting the perfect route from automobile clubs, online mapping services, or road atlases, many of which mark scenic routes. In addition, many hotel and motel chains publish free directories of their locations all over the country. Pick up a few of these to tuck in the glove compartment. There's hardly a corner of Europe that can't be reached by train, and riding the rails in Europe is a cultural experience in itself.