Ostia at Roman times worked as a port. Goods arriving from the sea often were then transported on the river Tiber.
Ostia was a very populated city and lived there many foreigners, sailors and fishermen.
In the archaeological there are numerous interesting mosaics and some of these reproduce marine subjects.
Fish are often fanciful to put fear to the simple people. Sometimes the fish seem ready to be cooked.
However the Romans sometimes bred fish and there were also scuba divers.
Fish are also represented in the mosaics of Pompeii (see photo wikipedia) and other ancient Roman cities.
Roman mosaic in Libya-old photo
Mosaic art was very important and popular for the ancient Romans. So in the mosaics were also represented many human activities.
Ostia antica -wikipedia
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