To any backpacking in Europe trip, you will hear people say that it is better to bring less to avoid carrying a heavy burden on your back. Tough the things you bring will be used for the quality of your experience, it could also wear your out more than the walking because of the heavy weight. Backpacking requires you to bring all your stuff wherever you go. So make sure that the most important stuff go into your bag first and leave all the rest behind. Anyway, there are always stores anywhere for you to bring anything that you might need. The technique is to balance things. Bring enough things that will make your trip comfortable but not too much to overburden you. Think of the essentials and consider what you really need for your travel. With a lighter backpack, you will not go through the point of cursing every time you have to carry the load on your back towards the next train stop.