I agree with all the other posters. I will add only that, although some things are closed and other things (eg. ferries in Greece) will be running a much reduced winter schedule, travelling to Europe in February or March gives you the opportunity to see some things more easily than you could if you were there in the summer. One example is Leonardo Da Vinci's Last Supper in Milan. If you are booking a reservation a month or two in advance for the Last Supper it can be difficult (or very expensive) to get a reservation to see it for the summer but a lot easier in winter (or at least, it was for me). Of course, the weather in Milan might not be great in February/March but you can spend other parts of your vacation further south in Italy where the weather is likely to be warmer.