My wife and I are going to Spain and Italy this August with our 3 kids. We plan on going to Barcelona, Venice, Florence, and Rome. Do you have a suggestion as to how many days we should spend in each? I guess enough days to fully enjoy each City. Perhaps squeezing a day trip to Cinque Terre and Siena. We are arriving in Barcelona on afternoon of August 19 and leaving Rome on Afternoon of September 4. So about 16 days or so. We plan on taking a flight from Barcelona to Venice and take the train down to Rome. Thank you!!!
4 days Barcelona
2 days Venice
4 days Florence (daytrip Siena)
2 nights Cinque Terre
3 days Rome
Personally it is busier than we would do for 16 nights. Unless there is a special reason for hitting Barcelona, I would save it for another trip. Fly directly to Venice for three nights - that is two full days of sightseeing in Venice. CT is too much (over six hours on the train) to day trip from Florence. So I would do 3 nights in CTerre, 5 nights in Florence with one day trip to Siena and maybe somewhere else - Pisa ?, and finally 5 nights in Rome and home. While in Rome you could do a day trip (a long one) to Pompeii. I would consider adding another night in Venice and take Florence to 4 nights. This does give you more flexible with your schedule.
Barcelona: 3 or 4 nights
Venice: 3 nights
Florence alone: 3 nights. Add one night for each day trip you intend to take from Florence (for example Siena, etc.)
Rome: 4 nights.
The above would be my ideal allocation for a trip of about 2 weeks. But depending on your personal interest, you could delete/add one night in any of the above and survive.
Thank you all for the wonderful suggestions! Please keep them coming! Grazie!