Rome to Barcelona

September is s great time for Sorrento and the Amalfi Coast, after the main blaze of summer heat has passed. I would head there after Rome, then Florence/Tuscany, and on to Venice. You can then fly to Barcelona from Venice.

Lucca is a good day trip from Florence. Verona is really beautiful. You can more easily see the possible affordable airline connections here: http://www.low-cost-airline-guide.com/en/airline-route-map.htm

Your decision comes down to "what do you want to do between Italy and Barcelona?"

You could certainly concentrate on Northern Italy, then fly to Barcelona, or you could come up with a Northern Italy plan, then into the French riviera (Nice), maybe Provence, over west to maybe Arles, then into Spain.

While I have spent maybe a total of a month or so in Rome over 3 trips, 7 nights may be a bit heavy for what you have planned. May be better spent on the journey to Spain.

That's a nice map that Mike linked. It reflects Vueling operating several possible routes between Italy and Barcelona, with Pisa being another of the airport options. Bottom line, you don't need to visit Milan for it's airport; only visit if you want to see the city itself.

You have a wealth of options there. I just want to mention that Pisa is normally handled as a day-trip from Florence. It only takes a few hours and is often combined with Lucca, which needs more time. You would not need a car for that day.

You can look at flight options from Italy into Barcelona on Skyscanner.

Thanks, skipping Milan is what we may do.

Go to the wiki page for the Barcelona airport. Toward the bottom you'll find a table with all the airlines and their destinations to/from El Prat. Anywhere in Italy is a good place to visit! I got a cheap flight from Bologna to Sevilla, spent the night in lovely Ferrara and took the shuttle bus straight to the airport or stay in lovely Bologna, even closer to the airport. Milan is a big airport, takes an hour to get there from the city.

With a rental car, I'd look for an agriturismo in Tuscany but near Umbria - day trips to Assisi, Orvieto and lots more options.