The Ancient Harbour is one of the quiet clues to why Ephesus became rich: this inland-looking ruin field was once the city's working edge on the Aegean. The coastline has shifted dramatically through silting, so the harbour area now reads as an archaeological landscape rather than a waterfront.
It is worth pausing here after the library and theatre because it changes the mental map of the site. Imagine cargo, pilgrims, officials, and theatre crowds arriving by water, then walking the processional streets that now sit far from the sea.