Central Europe: Help with a four-week itinerary

A pretty good plan.

You selected an itinerary with a lot of cities so you will be moving a lot between cities, however both legs of your trip (In the low countries then central Europe) the cites are relatively close together.

Dubrovnik was a great city, but we did it in one day, of course, you may have other places to visit nearby. Never been to Plitvice, but enjoyed Split. Nothing special about Zagreb.

You may wish to spend more time in places like Budapest, two days is short, I suggest three days. Also two days in Berlin is short, can you go to three.

Perhaps you should pick either the low countries or central Europe, that way you will have more time, whatever places you go. Plan on coming beck to Europe, most people do.

Oh fantastic. Actually thinking of dropping the Northern bit and adding Hallstatt and Cesky Kumrov. And buffing up Berlin and Budapest. You're saying we can shave a day off Dubrovnik on the itinerary?

If I was young, single and somewhat of a bohemian, I'd be spending my time in great cities like Amsterdam, Berlin, Prague, Vienna and Budapest. And I might throw Munich in there too. Forget the rest.
You never know what you are going to run into when you're young and backpacking Europe.
We're going to be in Budapest again next month, and are looking forward to visiting their Ruin Pubs. If you started your trip there, you may not make all your planned itinerary. They're perhaps the top honkey tonks in the world. All of the above listed cities are incredible, lively towns.

I think you have been a bit light on with time at most of your destinations. Dropping Croatia would free things up.

Aachen - 3 nights
Gent - 4 nights (days to Bruges, Brussels)
Amsterdam - 4 nights (day to Delft)
Berlin - 4 nights
Prague - 3 nights
Salzburg - 2 nights
Vienna - 3 nights
Budapest - 4 nights

I would cut Salzburg. It's nice enough, but it's a bit out of the way and that will give you a little more time for Berlin and/or Budapest, both of which need more than 1.5 days (the most you'll have with a 2-night stay). David's given you a hint to fewer hotel changes - in Belgium, stay in Ghent which is between Brussels and Bruges (and cheaper), then day trip to the others. Ghent is a university town, less touristy, more possibilities in the evening for eating and drinking. Netherlands - Delft is a nice 1/2 day trip from A'dam. I haven't been to Croatia, so I don't know whether it's worth skimping on the great cities for a few days there. I just happened upon this Lonely Planet article which recommends 7 days for Zagreb to Dubrovnik and sounds really nice.

Allow 2-3 nights for Frankfurt. There are enough sights to easily fill 1.5 days in the city, and nearby Mainz and Wiesbaden are worth visiting too.

I would hate to skip A'dam because it is both a great city and unique. I wouldn't hesitate to drop Belgium. If you skip Austria, you could stop in Bratislava for 1-2 nights between Prague and Budapest.