Polish Trains

Polish train tidbit:
IC (intercity) - take it whenever possible, or else you get stuck on a ...
POS - doubles your train journey time, and you only want to take a ...
OSO - for short trips because they've got hard seats and stop at every station

My train to Poznan from Krakow took almost 7 hours, when in comparison, it only took me 3 hours to get from Warsaw to Krakow, and they're about equally distant.