Germany recommendations - with car via Eurostar?

[Germanymunch]

Hoping to get some ideas for teens in Germany - one very interested in food, both about to start studying History GCSE. I've only ever been to Berlin so a bit out of ideas and hoping some people might give us some places to drive to and stay that would be interesting? I'd like lakes, beaches and old buildings if that can be tied in too.

Munich would be a good option. Your teens might enjoy watching the Eisbach surfing, Time Ride VR history experience, BMW factory tour and Museum of Technology and Science (very interactive). For a foodie, Viktualienmarkt is amazing and for history, Dachau Concentration Camp is less than 30 mins from the city centre.
For old buildings, there’s the famous Munich City Hall (we did an amazing Third Reich tour), Nymphenburg Palace and you could easily do a day trip to Neuschwanstein Castle and lake Eibsee.

Go down to the Bodensee (Lake Constance), via Eastern France, and then Freiburg. It's beautiful in summer, and there is so much to do for active teens - lots of lake swimming (& thermal pools) and cycling. On the history side, you can go over to Friedrichshafen by boat to visit the Zeppelin museum. Base yourself in Konstanz, which is a lovely small city - some of the buildings date back to the 1400s.

I suggest a base in Freiburg. Check that your accommodation comes with tourist tax which will give you Konuskarte = free local public transport!
Lots of activities and places to visit!

Then take a day trip to Lake Constance. Pile Dwelling Museum is well worth a visit for your Stoneage fix.
You can go to Alsace and visit Mont Donon and little Donon for some WW1 history.

There is a Schloss in Rastatt or Karlsruhe (accessible by train) to visit for a bit of glamour.
And if you need to jump back a bit in time, go to Baden Baden (by train) or Kaiser August (Switzerland) for a few Roman ruins with a difference!
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Had a very good family holiday in Heidelberg a few years ago, also Alsace/Switzerland/Germany triangle good with a car.

Went to Cologne a couple of years ago and frankly it was pretty horrible: dirty, slightly scary at night, massive amounts of aggressive beggars, felt like it had really lost it's way so wouldn't recommend at all.

Trier is a lovely base and from there you can visit the beautiful towns along the Mosel and even take a trip to Fantasia Land.

If going with a car I would suggest traveling through the Black Forest region ending up in Freiburg or Lake Constance. Berlin and Munich are easily accessible by air so you could do that anytime.

Do a loop, start with cologne maybe as an easy hop from the tunnel, head across to Munich perhaps (biggest drive) then up to fussen for the castles, perhaps Nuremberg through Black Forest (titesee is nice place to stop for some healthy walking type pursuits) then I suggest europaparc which I prefer to Disney and finally Aachen which I loved.

Oh and I forget Heidelberg that is brilliant too

How long will you go for? That could make a difference as to how far it's reasonable to travel.

Thank you so much for these amazing suggestions! Am now wondering whether to fly in and hire a car. Very much the first stages of planning so not sure how long to go for or costs yet. If anyone has any affordable suggestions for accommodation or a rough spend idea for 2 adults and 2 teens that would be fantastic!

We drive sometimes and others we fly and rent a car.

When we drive, it's doable to go to Heidelberg/Black Forest/Palatinate (Pfalz).
For Frankonia (north of Nürnberg) we did one overnight stay.

Lake Constance, Oberbayern (south-east of Munich) and Northern Germany (Hamburg, Baltic Sea) we flew and had a rental car.

We recently started using the flexi Eurotunnel tickets, more expensive but you cut on waiting times as you just hop on the next train instead of waiting.

S/C costs vary a lot, for a two bedroom flat you can have everything from €2000-4000 for two weeks.

We use Vrbo a lot and there is plenty of choice but you need to be fast, lots of good places are booked out long in advance.

We did one holiday and flew to Karlsruhe Baden Airpark (Ryanair) and hired a car.
We stayed in a self-catering flat in Schluchsee... so a bit of a drive to your accommodation.

Not sure about costs, as this was over 10 years ago!

If you want to fly in to Lake Constance, the nearest airport is actually Zurich. From there I would take the train, & then rely on the excellent (& free, courtesy of your tourist tax) local buses to get around. We stopped hiring cars because they never moved!
Or you can get cheaper flights to Basel - quick bus into the city and then, again, very good rail connections to Zurich and Konstanz.

There used to be a limited number of summer flights to Friedrichshafen, but you are a bit more limited for days out from that side of the lake.

Be aware that approx 10th August is the Seenachtsfest (lots of activities and huge fireworks display) and hotels and apartments book up quickly for that weekend.

Costs are as much or as little as you want to pay, tbh. But stay on the German side of the lake, as Switzerland is crushingly expensive!

We flew to Stuttgart when we went to Lake Constance.

En route to Germany swing by Luxembourg. Lovely little country. Lots of pretty towns with castles, beautiful countryside. Just over the border into Germany Trier is well worth a visit built by the romans, and very well preserved ruins.