We walked 20 km today, breaking our previous record of almost 19 km yesterday, but before that all the way back to our first full day in Paris at 18.5. Over half of it we did this morning at the ruins of Ostia Antica, a preserved city ruins dating back to the 7th century BC (though none of those structures remain). They say the Roman empire had its first colony at Ostia, which had been situated where the Tiber River met the sea, though now the beach is 3 km away. It provided access to the salt trade early, and then later in the empire the flow of grain to be distributed in Rome city.
The city in ruins is huge, sprawing, at one time inhabited by 50,000 people. It is very well-preserved, apparently almost as well-preserved as Pompeii. Many of the tile mosiacs remain intact, including within the baths of Neptune, (the public Roman bath), within another private batch, which we were able to stand in, and in a fish market, where they had one of a dolphin eating an octopus. In the baths the mosiacs featured Neptune with fish and mermaids and were really cool. We bought an excellent guidebook at the entry to Ostia that had tranparencies overlaying photos of the ruins to show what they'd have looked like at the time (general 150-400 AD for most standing ruins). It was excellent after seeing the Roman Forum yesterday, and very few visitors there, it being a bit of a ride out of the city on their outer Metro line.
After a several-hour break during the heat of the day, we went to the Pantheon to see inside (incredible) and then up to Augustus' Arc of Peace, then onto the Spanish Steps. We found a Chinese restaurant for dinner because we were tired of Italian food.
Tomorrow we leave Rome, see the Leaning Tower at Pisa where we'll regain our car (I haven't loved the train travel, to be honest), then to sleep in a "spa town" between Pisa and Florence. The next day we're to do a science museum in Florence, and then head on up for two nights in Venice. Not sure about Internet access because this was an unplanned section of our trip.