Moved to europe from states with 2 dogs (1 chihuahua and 1 60lb dog). We just checked all of the bags. Big dog was checked like a bag and put in cargo in his sky kennel. Tape food to the outside of the pen and put one of those hampster water things on the cage for him. Dont give the dog anything to put em out (slepping stuff, allergy things, etc.) just let them be as normal. Our's peed in his pen on the way there (was a 10 hour flight). Chihuahua went in the cabin with us. Europe (we were in Germany) was so much easier with dogs. Dogs get an EU pet passport (go to vet when you are there and show them all your vaccines and such and they will issue one). Vet's are soooo much cheaper in Europe, a trip to the vet for both was 50 euro total, no joke.

Can't speak for southern europe but it was also nice cause we took our dogs everywhere, on the train, on the bus, etc. Hope that helps