GERMANY - 8 DAY DRIVING TOUR IN AUGUST 2014

While I am all for driving in Germany and whirlwind tours sometimes... I just don't see this as being anywhere near feasible. I suggest you take a good look at a map and driving times and then figure out how much time you would like to spend at each location. I think you can either do Berlin and surrounding area or the Munich area, but definitely not both unless it will be a drive-by from the autobahn. If you decide the south you could do Frankfurt, Stuttgart, Heidelberg, Neuschwanstein, and possibly return your car to Munich on your way out... but this will still be a ton of driving with little time to enjoy much of anything. Do you want to just drive into Switzerland, or is there a location you want to see there? Expensive... even to drive there as you need a vignette (can't remember the cost) Try to come back with the 'must see' locations and whether or not you can fly into Frankfurt and out of Munich. (or Berlin if you want to see that)

Even though you're flying into Frankfurt, we'd skip visiting the city on this short of a trip. It's easy to get right out to the Rhine Valley or other first stop by either train or car (train about 1.5 hours to St. Goar or Cologne, or 5 hours to Berlin, etc). Two nights at most stops will help you avoid exhaustion, and I'd rather have three or four nights in Berlin (and no car there).

I don't think that list is realistic in 8 days. I would go Rhine Valley>Heidelberg>Stuttgart>Munich/Neuschwanstein Castle. Cologne is a little out of the way and Berlin is way out of the way.

Are you planning on flying out of Frankfurt as well or flying out of Munich/Berlin at the end of the trip?
Does 8 days mean 8 nights or 9 nights?

Thanks for all the great advice. We will actually be staying 9 days, 8 nights. Also, we will definitely be flying in and out of Frankfurt. Casey - I like your itinerary. Would you mind elaborating a little more? Where is the best place to take a tour on the Rhine and should we head there the first day?

If it was me, I would use Frankfurt as a hub. From here, you can go spend a day on the Rhine, on a 2nd day go to Heidelberg, and on the 3rd day, go to Büdingen (this is a town just like Rothenburg, only without the tourist buses and souvenir shops). On the 4th day, head down to the Munich area. From here, you could do day trips to Neuschwanstein, Salzburg or Garmisch.
http://www.buedingen.info/en/

Frankfurt has some lovely residential neighborhoods, where you can stay in a B&B, but also have easy access to the public transportation.
http://www.hotel-am-berg-ffm.de/
http://www.hotelbeethoven.de/
http://www.dirazi.de/index1.html
http://www.kleine-villa-frankfurt.de/index.html

This saves you from moving from hotel to hotel, which takes up time that frankly, you don't have. The Rhine, Heidelberg and Büdingen are all just 1 hour by train from Frankfurt.

The trains here are very easy to use and first time travelers shouldn't have a problem using them, rather than driving. If you want to do some wine tasting, it is important that you don't drive.

Is there a reason to visit you want to visit Stuttgart?

My husband and I are planning something similar for June - in and out of Frankfurt, renting a car, small towns and villages, etc - the one difference is we've been to these areas quite a few times already. Like the other people who have answered your question, I think you are trying to do far too much. I'd drop Cologne, Berlin and Stuttgart for this trip. I'd suggest you focus your first couple of days in the Rhine Valley - the suggestion to stay in Bacharach is a good one - do a river cruise, wine tasting, etc. Then do a meandering drive with one or two one-night stops (there are lots of wonderful towns to choose from) south towards Munich. Spend a few nights in Munich and then head south toward Fussen (we much prefer sleeping in Oberammergau or Mittenwald over Fussen) for another few nights. On your last full day, drive back towards Frankfurt and stay in a town relatively near the airport (we love Heppenheim) depending on the time you fly out.

How about this as a starting point:
Day 1 - arrive, pick up rental car, drive to Bacharach, explore town or river cruise if you are up to it (night Bacharach)
Day 2 - river cruise, wine tour, or drive along Mosel (night Bacharach)
Day 3 - drive to Rothenburg, explore Rothenburg, Night Watchman's Tour (night Rothenburg)
Day 4 - drive the 'Romantic Road' to Munich - stop in a few small towns along the way (night Munich)
Day 5 - explore Munich's city centre (night Munich)
Day 6 - drive to Oberammergau, meander through Bavaria, visit Andechs, Wieskirche, Ettal (night Oberammergau)
Day 7 - visit Neuschwanstein Castle, Linderhof Castle, etc. (night Oberammergau)
Day 8 - meandering drive to Heidelberg or other town near Frankfurt Airport (night near Airport)
Day 9 - drive to airport, drop off rental car, fly home

This itinerary assumes you are like us and driving is part of the experience for you. We love getting off the autobahn and spending half a day getting from A to B and discovering what is in between, which is what it sounds like you are looking for. This itinerary should give you a good balance between driving and visiting towns/sights with more than one night in most places.

Good luck planning and enjoy your trip!