[/nq] A port is place on a waterway with facilities for loading and unloading ships - so ports can exist on rivers and canals as well as at the seaside A harbour is usually (but not always) more of a natural feature, like a bay, where ships can tie up, but is not principally for taking on cargo. Port suggests a fairly significant commercial operation; many harbours are small, used only for local vessels or leisure use. On the other hand, a port might be the commercial part of a larger harbour.
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