Munich to Amsterdam Itinerary

Instead of Koblenz, stay in Boppard. It’s a much more charming town. Marksburg castle is a great choice. From Boppard, take the train to Bacharach. Explore a while then take the boat back to Boppard.

Rothenburg really shouldn’t be an “on the way” stop. You’ll wish you had more time. I would drop Nuremberg, add a night in Rothenburg and add a night to Boppard.

The Romantic Road was disappointing after spending a week around Salzburg. Head to that area if you want spectacular scenery and castles.

Do you plan to travel by train or by car?

Boppard is a great choice. The town has a nice river city buzz and lots of choices for food. But, I do I think there's too many steps in and around Marksburg Castle for the two younger children. In any case, have a wonderful family trip!

Thank you!

We will travel all by train (bus when needed). We want to avoid needing car seats.

I absolutely love Salzburg but we have been there and are hoping to explore some new areas.

Do you suggest Romantic Road stops (Wurzburg/Rothenburg) over Nuremberg? I was afraid the Romantic Road stops might start to feel redundant. I'll do more reading about this section next.

Looking at your actual time for seeing/doing here...

12 days, minus Day 1 and Day 12, minus 50% of Day 2 (arrival, transfer, hotel check-in,) minus .5 days for Nuremberg > Koblenz (transport) + minus .5 days for Koblenz > A'dam (transport) = approx. 8.5 days

Your travel goals seem too demanding for this period of time to me, even if you were a group of active adults. 3 and 5-year-olds, even if they are generally "good travelers" at home, will likely require more attention and more down-time than they might if they were at home. My daughter was 9 and already well traveled back home when her first trip to Europe took place, and while thrilled to be going, she still found the travel and the cultural changes intimidating and unnerving to some degree.

Leaving out the food and beer... you are looking for... "local culture, nature/hiking... history, small dose of museums, and exploring small towns." IMO Munich and Amsterdam seem to lie outside your stated interests and are very likely too demanding for your family and the short time you have. My take is also that your itinerary appears to dedicate days 1-2 mostly for the half-hour tour of Neuschwanstein plus maybe Hohenschwangau? This day trip is roughly 5 hours of transport on a day outing. I think your kids will have plenty of time to see it on their own at some later point in life when there's more time to dedicate to the other sights in the German Alps.

Suggest this modified itinerary instead...

DAY 1: Arrive MUC, transfer to FREISING (15 minutes by train or bus.)
Freising is a small, walkable, attractive Bavarian town with good railway connections (if you need them) and a good place to get your bearings on Day 1 and settle in after an overnight (and perhaps sleepless) flight. Read below on things to do that day, food, beer, hotels:

https://www.tripadvisor.com/Tourism-g198549-Freising_Upper_Bavaria_Bavaria-Vacations.html

DAYS 2, 3: Rent a car. Drive to ROTHENBURG for 2 nights. Not my favorite place, but you want to go there, and it's a small town with some history to it. Take a day trip by car or by train on Day 3 to Bad Windsheim for the Franconian Freilandmuseum, where you really get to see and experience local history. AND it's a great spot for traditional food and beer-lovers.

https://www.tripadvisor.ca/Attraction_Review-g198421-d284746-Reviews-Frankonian_Open_Air_Museum-Bad_Windsheim_Middle_Franconia_Franconia_Bavaria.html

https://www.beerwanderers.com/freilandsmuseum-kommunbrauhaus-burgerbrau/

DAYS 4, 5, 6: Drive to BAMBERG (3 nights) stopping on the way in the small Main River old-world towns of Ochsenfurt, Sommerhausen, Marktbreit, and/or Iphofen. Tour Bamberg on Day 5; maybe drive to Staffelstein to see the incredible Vierzehnheiligen. Day 6: Day trip by train to Nuremberg for the sightseeing you planned.

DAYS 7, 8, 9: Drive to B0PPARD (3 nights), stopping in Bacharach for a look around town on the way. This is where your nature and hiking come into play (Rheinsteig / Rheinburgenweg trails.) Other options: Rhine Cruise / Marksburg Castle / outings to Rüdesheim, Oberwesel (town wall walk), St Goar (Rheinfels Castle) / "Park am Mäuseturm" in Bingen (riverside Playground/Park) / Loreleybob (summer bobsled run)

Day 10, 11: Drop car in Koblenz or Bonn; train to the Netherlands. I'd avoid A'dam personally with young kids. Not too far are other nice towns. You might enjoy the handsome old town of Naarden, near Bussum, less than 1 hour from Schiphol airport.

I did not see your note on car seats prior to my post. I think the car seats would be worth the trouble, personally, for several reasons. But the suggested itinerary could be adapted for train travel by dropping a few options here and there as most of those places I identified are accesible by train.

Day 3: Munich, daytrip to Fussen

That's 5 hours on a train in one day.

Having just done Rothenberg>Fussen>Munich by car, I would've suggested staying overnight in Fussen. But I think most trains will take you back to Munich to get to Nuremberg. Either way, that's a lot of travel for three kids. I might recommend forgoing Fussen. Keep in mind your kids might be wiped after the flight, so you might not get to see much of Munich Day 2.

Day 6: Nuremberg, daytrip to Bamberg

I originally had Bamberg on my radar. Unfortunately, it didn't look like there was much to do for my kids. As much as I wanted to drink rauchbier (didn't really see smoked beer anywhere else on our trip) and walk the brewery trail , I chose Rothenberg instead. Much more kid friendly with a Christmas store and museum. But it's not easy to get to by train.