Two places that make a pleasant change from the centre of Rome - both of them easily visited by train as day trips...
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Ostia Antica:

Enjoyable for the medieval borgo, adjacent to the Papal castle, and also the extensive remains of the port city that
once supplied ancient Rome - whilst not a patch on Pompeii and sites around Vesuvius, those are still worth a look!

For more details, see.... http://www.ostia-antica.org/touristguide.pdf

And for photos of the nearby ruins of Portus, a contemporary town constructed around Trajan's hexagonal harbour after
the one at Ostia had begun to silt up, see __ http://www.pbase.com/isolaverde/portus
.
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Bracciano:

Go for the Castello Orsini-Odescalchi - where Tom Cruise and Katie Holmes married - and, on the shores of the volcanic
crater lake at Vigna di Valle, a fine museum with racing seaplanes that competed for the Schneider Trophy and other
unusual aircraft. For details ___ http://www.aeronautica.difesa.it/museo_storico_eng/Pagine/default.aspx

Otherwise the local tourist board website is on ___ http://www.turismobracciano.com/

Click the individual images for larger versions, lots of them with a few notes and comments!