The Haven Ports are a group of five ports on the East Coast of England, these are Port of Felixstowe, Port of Ipswich, Harwich International, Harwich Navyard and Mistley. However, traditionally, only the three deep-water ports of Ipswich, Harwich and Felixstowe that are on the confluence of the River Orwell and River Stour have been known as the Haven Ports.
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Haven ports Wikipedia(Text) CC BY-SA