I guess some of it depends on budget too, I can thoroughly reccomend Crete and if I was in Italy I would be wanting to see Etna and the volcanoes.
There is a good B&B in Provence in France that you can stay at and do astronomy too, you can do a little course or just try your hand at observing and imaging plus they offer more than just astronomy related activities.
http://www.sunstarfrance.com/
Plus there are some good observatories around that area.
Belgium is nice I guess, maybe. Not much in the way of astro related things but lots of beer and that suits me fine
