I am in need of cost, time and distance/directions between Ryanair Rome airport Rome to the Camp de' Fiori section of Rome, and the Ryanair Venice airport (I know it is fairly far north of Venice) to the heart of Venice.
Don't know about Rome, but there is a bus service that only costs a 5 Euros - 9 Euros return - and takes you from the Treviso airport to Piazzale Roma in Venice.
It's about the same for Rome, maybe a little more. I've never paid more than 14euros RT.
Depending on the time of your flight, and other flights leaving about the same time, the bus from Venice to Treviso leaves about 2½-3 hrs before flight time.
For arrivals at Treviso, the bus leaves the airport 20 min after landing time and gets into Venice 1hr10min later (1hr30min after landing).
The buses from Ciampino leave 20min after landing and takes 40 min (arriving in Rome 1 hr after landing time).