The eastern coast of the Aegean comprised ancient Ionia, one of the great centres of Greek culture (architecture, philosophy, religion). In the Roman period, most of Ionia became the province of Asia, centred around Ephesus as the provincial capital. It continued to be a major centre of influence, though many of the formerly independent cities (Miletus, Priene, Magnesia, Smyrna, etc.) were downgraded or faded away (in some cases, because the harbours became so badly silted up that they were unusable).