Hallo Krulle,
Poland is very nice country with very welcoming people and Krakow is a 1000 years old city really worth to see. I was born in the area of Mazury (very nice with al this lakes and lots of green) and lived in Gdynia in North Poland. The "Pomorze" -area neer the Baltic See is also very nice to come in the summer. And not to forget, Poland has mountains also! You can go to the Zakopane (in the Tatry- mountains). I haven't been yet to the Polish mountains :-(, but they are (so I've heard) very charming ;-)