Harwich Haven Authority (HHA), an organization based in the UK, is tasked with safeguarding the best natural haven on the east coast of England. Its jurisdiction covers the River Stour, the lower part of the River Orwell, Harwich Harbour and an area to seaward extending 12 nautical miles from the harbor entrance and covering 150 square miles.
The HHA provides services for shipping using the commercial ports of Felixstowe, Ipswich, Harwich International, Harwich Navyard and Mistley and also boarding and landing services for the rivers Thames, Medway, Blackwater, Colne and Crouch. The HHA provides a web service that lets users access the data kept by the organization. Data includes anchored ships, arrivals, forecasts, tides, traffic and more. The API uses SOAP protocol and responses are formatted in XML.