Ruins of the Theatre of Ostia Antica
Ostia is Latin for "mouth", the mouth of the Tiber. This Roman city was in ancient antiquity situated at the mouth of the Tiber River and was used as harbor for Rome which lies some 30 kilometers to the east. The shoreline moved seawards, due to silting, from the Middle Ages until the 19th century. Therefore Ostia is today still lying next to the Tiber, but at a distance of some three kilometers from the beach. Ostia had a population of over 50,000 during its peak and the ruins are widely spread out. Marble stripped from the buildings in Ostia was reused in the cathedrals of Pisa and Florence, and other cities.
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