Thanks for the replies
Definite musts are:
Amsterdam
Berlin
Prague
All three of them are really cool cities and worth a visit.
In the Netherlands you might also consider spending a night in Utrecht. It's not that far away from Amsterdam (20-30 minutes by train) and has similar architecture like in Amsterdam. It is a typical "student city" in the Netherlands with fun night life.
I currently live in Munich, let me know if you need detailed help. Depending on when you're visiting I might even be able to guide you around a little.
Looking at spending maybe 5-7 days in each of those at the moment, but seeing as I'm in Amsterdam on a tour before this as well, I like the idea of going out of the city a little bit.
But how I think Czech beer really stands out is the price, you can get 0.5 litres for around 1 euro (usually less) pretty much anywhere (except for aiports lulz). Again, not much knowledge about prices in other places, but Marawana was really surprised by the price.
So yea, wanna a reason to travel to Czech republic? Beer!
For some unconventional places to visit, there is 4D cinema in Prague and also a 'wind tunnel' (you step into a room with has a huge fan on the floor and it holds you in the air like that). I guess these are more of activities than places tho. Don't think i can suggest much more, other is just basic sight-seeing stuff[1] and i haven't been to Prague that often to know some other cool places to go.
1.. Chalres bridge, Petřín Lookout Tower, Prague Castle
Yeah I definitely won't be missing out on the cheap beer, very keen on that! Yeah sightseeing stuff I'll probably do for a day or two, so yeah want to fill up the rest of the time with activities/drinking (of which the wind tunnel will now be one... haha).
Cologne + Phantasialand (theme park)
and / or
Hamburg + Heidepark (theme park).
Europapark is nice too
Amsterdam, Berlin, Prague, Cologne, Hamburg, Vienna, Salzburg, Munich
I'll keep those in mind as at the moment I'm not directly going to either Cologne or Hamburg, but if I end up with extra time I assume trains aren't too expensive to make the trip? More likely would be Hamburg. I wasn't planning on stopping in Salzburg, what is there to do/see there?
Dresden is nice
I think I'll be stopping there on the bus on the way to Prague, so won't have much time to do anything there except a quick walk around.
If you can make the trip to Switzerland I highly recommend it. I've been to most of the major spots in Europe, and Switzerland was right near the top. Specifically I really liked Engelberg. Went skiing and hiking. Lots of fun.
For stuff on your list, Prague, Amsterdam, and Munich would be the top of my list of the places I've been.
I'll be there for a couple of days on a tour before I start backpacking, I think in Lauterbrunnen, so I'm hopefully going to go skydiving and maybe skiing there, and then whatever else the tour ends up doing of course.
If only you were going late June </3
I'll still be there haha, gonna be in Iceland late June, then following Tour de France around in July.
So from everyones suggestions so far, the cities that I need to spend some decent time in are Amsterdam, Prague, Munich and Berlin (and Vienna?). Seeing as no-one has commented on it either, is Venice worth going to twice? I'll be there on the tour before this stuff for a couple of nights to do the typical tourist stuff, but would rather spend time elsewhere if that is going to be enough.