Porto Santo
Keva Magera
The train from Fiumicino Aeroporto (FCO) station to the Orbetello-Monte Argentario station requires actually two trains.
The first train goes from the airport to the city of Rome.
Once in Rome you change trains to go up to the coast to Orbetello.
The specific station where you make that train change in the city of Rome varies depending on which train and time you take it.
Some require the change at Roma Trastevere station, some at Roma Ostiense, some at Roma Termini (which is Rome's main station)
Go to the website below and enter
FROM: Fiumicino Aeroporto
TO: Orbetello-Monte Argentario
DATE: enter the date of your travel
TIME OF TRAVEL: Approximate time of travel, or put very early in the morning to see all trains.
The website will give you many solutions. Depending on the solution selected you will have to change trains in Rome at the specific station indicated (see the details info to see which one).
Once you alight the train at Orbetello you can take a bus to Porto S. Stefano.
The bus schedule is below.
-del-giglio-info/orario-autobus-orbetello-scalo-porto-santo-stefano.pdf
and also here
-bus.it/en/timetables.html#modTimetables_collapseExtraUrbanLine
Select Suburban services, then Servizi Extraurbani GR, then select bus Oo1 to dowload the timetable in PDF