11 days in southern Germany/Austria

Are the kids boys, girls, one each ? If car enthusiasts, consider Stuttgart andnthe Metcedes and Porsche museums.

In Austria do a salt mine tour and the ice caves at Werfen ( south of Salzburg )

Better to fly into Munich.

Bavaria is my favorite area of Germany, with the Rhineland and Berlin second and third.

Suggest 3 days in Munich to see the sights there as well as Dachau.
Another 3 days in Salzburg and nearby Berchtesgaden (Eagles Nest).
Then head down to Innsbruck, Austria for a couple of days, then back to Germany visiting Fussen and Garmisch for 3 days.
Then head up toward Augsburg on the Romanic Road, stop in Oberammergau where the Passion Play is given every 10 years, stop in Augsburg for a half day, then up the Romantic Road to Rothenberg ob der Tauber.
That will take the rest of your trip.
https://www.romanticroadgermany.com

Use TripAdvisor to see that is best to see in all these places.

How old are your teenagers? What are things you like to do as a family? What is on your wish list to see? This will help us better give you suggestions on things that we have done and that you might enjoy.

Also, have you already purchased your air tickets? Knowing this will also help us help you find the best path for your time in Germany.

Cars vs Trains - you will find many opinions in this forum about the joys and headaches of both. For us, we love to drive, but it is the parking situation that gets us every time. Most of our funniest stories (while not funny at the time) come from either driving or parking. If you park in a parking garage, just remember to pay your ticket at the kiosk first before trying to leave or you will have some angry Germans honking at you while you scramble to the kiosk. Also if you decide to drive, look for hotels that have parking. Cute little hotels in small towns are often in a pedestrian zone, so parking is tricky. You will also not want a car in a big city. But once we know more of your thoughts, we can help give suggestions.

Wow, thanks everyone already! We already have flights in/out of Frankfurt due to $. 2 girls (16 & 19). Planning to do the Porsche museum on way between Frankfurt & Munich. Interested in all things WW2 (but don't want that to be the whole trip), visiting Dachau and Hofbrauhaus. Want to see some of Ludwig's castles, would love to stand up paddle board somewhere. 19yr old and I did Sound of music Tour when she was 10, not going to do that again this trip. I like the idea of three 3 night stays, packing & unpacking over and over is stressful.

Planing to go south by car and back to Frankfurt seeing Porsche Museum and some WW2 sites I would recommend to go one way via Stuttgart and the other way via Nuremberg
For ex
Frankfurt-Heidelberg-Stuttgart-Füssen-Munich-Nuremberg-Rothenburg-Frankfurt

I would do
day 1 Frankfurt

day2 Frankfurt- Stuttgart 2-3 hrs drive stay in Stuttgart or nearby 1-2 nights See Heidelberg or Speyer on the way
nextday Stuttgart-Füssen 2-3 hrs drive stay in Füssen or nearby 2-3 nights See Ulm or Kempten on the way
following day Füssen-Munich2 hrs drive stay in Munich or nearby 2-3 nights
nextday Münich -Nuremberg 1,5-2 hrs drive stay for 1 night
lastday Nuremberg -Frankfurt 2,5-3hrs via Rothenburg longer so perhaps dstay for 1 night in Rotheburg in between

Makes it 11nights

See along the way Frankfurt-Stuttgart

Heidelberg
https://www.heidelberg.de/english/Home/Visit.html

Speyer
https://www.speyer.de/en/tourism/
https://speyer.technik-museum.de/en/

I would recommend 2 full days in Munich and Füssen

Do daytrips from Füssen to Plansee Schloss Linderhof, Kloster Ettal ,Oberammergau and Wieskirche a curcuit 100km drive

Plansee
https://www.tyrol.tl/en/highlights/nature-and-landscape/lakes/lake-plansee/

Schloss Linderhof
https://www.schlosslinderhof.de/englisch/tourist/index.htm

Kloster Ettal
https://www.kloster-ettal.de/

Wieskirche
https://www.wieskirche.de/files/Rundblick/index.html

Do a boatrip on one of the lakes one day, Go with cable car up Tegelberg
And of course see the Castles and Alpsee

Tegelbergbahn
https://www.tegelbergbahn.de/de

Alpsee
https://www.hohenschwangau.de/natur-umgebung/alpseebad-in-hohenschwangau

Daytrips from Munich 1hr from Munich

Lake Chiemsee and the isles Herrenchiemsee and Frauenchiemsee
https://www.chiemsee-alpenland.de/entdecken/chiemsee

or Tegernsee
https://www.tegernsee.com/

Munich- Nuremberg
https://tourismus.nuernberg.de/en/

Rothenburg
https://www.rothenburg.de/#

Last but not least
A daytrip from Frankfurt to a Roman Fort and a Folk Park 30 minutes north of Frankfurt

Saalburg
https://www.saalburgmuseum.de/en/

Hessenpark
https://www.hessenpark.de/en/

No disrespect to Frankfurt, but do you know what you want to see there? It is the most convenient city for me to fly to/from the US, but I don't find much to do there that can't be done equally well in another city. I ask because you can save some time by heading right from the Bahnhof at the airport to your first destination, such as Stuttgart. This also avoids driving the first couple of days while recovering from jet lag.

Regarding car vs trains: trains take you right to the city center and allow everyone to be on wi-fi, nap, read or have a snack while traveling. Cars give you the chance to get off the beaten path. If you drive, consider staying in suburban hotels with a U-Bahn stop nearby. This negates the need to drive into city centers and gives your group some flexibility for family members doing different things.

No disrespect but I wont drive direct after a long transatlantic flight a long distance on the Autobahn
Better stay in Frankfurt for one night and relax or do a short drive to the mentioned Folk Park and Roman Fort in the Taunus Hills 35km north of Frankfurt Airport
You can also stay in the Guesthouse in the Folk Park for the night

See HessenPark Country Hotel

Interested in all things WW2...

Once you firm up the cities in which you'll be staying, there is a web site your see. It's named thirdreichruins.com. There are photos of places in many cities taken shortly after the was, and photos of the same places taken in more recent time. Very interesting constrasts.

We did a trip recently flying into Frankfurt and then ending in Salzburg with a quick flight back to Frankfurt.We used trains to move between our destinations.

Instead of doing a day or two in Frankfurt, a friend recommended Wurzburg which should be an easy train ride from Frankfurt’s airport. Beautiful mid-size city with some great sites like the Residence and Fortress. Tho holiday demand plus DB issues plus flooding elsewhere led to challenges with our train trips…reminded us of NJ Transit in all the wrong ways :)

Wurzburg is a short one-hour drive from the Frankfurt airport. Motel One has built a hotel there and I would suggest you take that hour ride and then spent the night there. Beautiful town, we spend two months there almost every year. Not covid 2020. Next day off to Rothenburg with a night stay there and then to Fussen for the castle touring and the night. Head across to Garmisch. You have the German Alps to play around in and some really nice towns. I would then head to Berchtesgaden for a couple of days and take the city bus to Salzburg for one of the days. Lastly, head up to Munich and drop your car off at the airport and jump a train from there to the Frankfurt Airport. The ride is about 3 hours. Go on YouTube and check out (Near From Home). Two vlogs that do Southern Germany and Austria. They have some great tips and areas for you to see.

thank you so much everyone!. any new ideas, keep them coming!

Here two videos about

Saalburg
https://www.youtube.com/watch?v=StDbii9Jtr8

and

Hessenpark
https://www.youtube.com/watch?v=tkgwUPle1yA

We are doing a similar trip this summer with two teens, although flying into Munich most likely. This looked interesting to us due to the views: https://www.grainau.de/en/zugspitze-cog-wheel-train#:~:text=The%20cogwheel%20train%20of%20the,Partenkirchen%20at%20the%20Zugspitze%20station.

We are thinking about a few days in and around Fussen / Innsbruck / Salzburg as well.

I am going to advocate for a much shorter travel circle than has been proposed here so far. 11 days should be spent with your feet on the ground rather than on the floorboards of your car. It's not as though Germany or even southern Germany is defined by Munich and southern Bavaria. Day 1 might well be compromised by flight delays, drowsinesss, jet-lag, etc. 10 real days of sightseeing in smaller towns... that is more easily accomplished with a much smaller travel circle. I can see a trip that connects these three zones...

1) Rothenburg/Würzburg + other Franconian destinations (Miltenberg? Dinkelsbühl? Iphofen? Bad Windsheim?)

2) Heidelberg, Speyer, Porsche Museum + other nearby places (Michelstadt? Bad Wimpfen? Burg Guttenberg Castle and Falconry show? Besigheim? Ludwigsburg Palace?

3) Rhine Valley River Gorge + Mosel River Valley, between Bingen and Koblenz: Castles, castles and more castles... (real ones) ... river cruises on the Rhine or Mosel Rivers... old-world towns like Bacharach, Cochem, Bernkastel, Rüdesheim, Oberwesel, Braubach... chairlift and gondola lift rides to scenic lookouts... biking and hiking options...Note that the Rhine gateway towns of Bingen and Rüdesheim are very close to FRA airport. See map:

https://www.rhine.apartment-listings.com/bilder-fotos/map/lageplan-bacharach-600-7.gif

https://community.ricksteves.com/travel-forum/trip-reports/baltic-germany-fachwerke-landesgartenschau

Skip down to subheading Fachwerkestraße.

We did Germany and Austria (and few other countries) in 2016 with our 3 teenage sons. My advice (obviously take into account the character of your kids) is to undertake some activities they would find exciting. Our sons loved Austria. One highlight was going paragliding. You sign up for tandem rides with a pilot. We used Flugschule Air Star - they were awesome. We took off from two mountains - Schattberg in Saalbach-Hinterglemm and Schmittenhohe in Zell am See. We stayed for two nights in Saalbach-Hinterglemm where the small hotel was part of a working dairy farm. There is also hiking ther on the Schattberg and mountain biking. There also might be a summer non snow luge/tobaggon run there. In the 90s as a twenty-something I went white water rafting the Austrian Alps - teenagers would love that. My boys really like Salzburg. The castle is a must see there and just walking around the old town is great. Going up the Zugspitze and sledding on the glacier in August was also fun. Pick one of King Ludwig II's palaces, I suggest Neuschwanstein. Teenages get bored with too many palaces. Do not do the Residenz in Munich it bored the tears out of my sons - too big - too many rooms with paintings of too many dead Wittlesbachs. Berchtesgaden which is close to Salzburg was fun also. The boys liked Kehlsteinhaus (Hitlers Eagle Nest) and hiking up by it. Konigsee by Berchtesgaden and the boat ride are great. Get off at the top of the Lake and hike to Obersee (light hike with great views at the end). Also the salt mine in Berchtesgaden was good. One of the favourites of all three of my sons was Hallstaat. We rented one of the small electric boats and spent a couple of hours cruising the lake. You are not bothered by crowds of tourists if you do this. Munich is also fun for teenagers. The legal drinking age for beer in Germany is 16. The beer gardens are a great place to eat - great food very reasonable price. I recommend the Augustiner Beer Garden in Munich. If you go, eat full serve as opposed to the self serve and ask to eat in the cellar, beer hall upstairs or restaurant patio outside. The shopping in downtown Munich is incredible and your teenages might appreciate some free alone time there. I think its safe and the old town centre is mostly car free. The Ratskeller Restaurant under City Hall in Marienplatz in the old town is a great restaurant with great traditional decor.

In Austria a real fun adventure is to drive the Grossglockern High Alpine Road and stay overnight in the town of Heilgenblut. Your teenagers will love the road, I think over 30 hair pin turns. Its very well maintained. If you go there make sure to stop at the Fuschertorl (restaurant there) and take the small side road from there up to the Edelweissspitze (highest point on the road) and also take the side road to the Kaiser Franz Josef's Hohe to get great views of the Grossglockner (highest mountain in Austria) and the glacier beneath it. The small town/village of Heilgenblut is one of the most picturesque in Austria in my opinion. Near Salzburg you can stay in the lake area just to the east. We stayed in St. Gilgen. You can rent bikes and bike around the lake to St. Wolfgang. June might be too early to swim in any of the lakes.