If you go to the Netherlands and wanna skate, Rotterdam's your best bet. The city was bombed by the Germans in WW2, so pretty much the whole city is paved and has a ton of spots, almost no cobblestones and shitty bricks. Other big cities like Utrecht and Amsterdam are really cool as well, but definitely harder to cruise, fewer spots and further between.
An other tip would be Prague, super fun, really beautiful city and really cheap. Enjoy!