We haven't been to Spain or France but our cruise took us the rest of the places you are going with the addition of Egypt. It was so much fun. Highlight was Mass at the Vatican celebrated by Pope John Paul.
Be sure to visit the Grand Bazaar and barter. I got a great leather purse for $30 after I bartered and he wanted $85. Beware of the good looking Turkish men who have families in the rug business
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We did a bus tour on the Amalfi coast and it is breathtaking. The ride was breathtaking too!
Eating in a seaside restaurant in Piraeus is unforgettable. You may have a feral kitty next to you waiting for your fish scraps.
You will have a wonderful time. Just keep your belongings close to your body.