Ocean power in New Zealand speed. Because the tidal speed doubles, eight times more tidal power can be produced at spring tides than at neap tides. The entrance to Kaipara Harbour, one of the largest harbours in the world, is a channel to the Tasman Sea. It narrows to a width of , and is over deep in parts. On average, Kaipara tides rise and fall . At high tide, nearly 1000 square kilometres are flooded. Spring tidal flows reach 9 km/h (5 knots) in the entrance channel and move 1,990 million cubic metres per tidal movement or 7,960 million cubic meters daily. In 2011,
Poland's Wedding to the Sea a merger of Wielka Wies and Hallerowo. In the early spring of 1945, a number of symbolic Weddings to the Sea took place along the Baltic Sea coast. The most well-known such ceremonies were on March 17, 1945, at the town of Mrzeżyno (Regamünde), and on March 18 at Kołobrzeg (Kolberg). This is what Polish historian Hieronim Kroczynski wrote in his book "Polskie Polskie tradycje morskie 967-1945" ("Polish Naval Traditions 967 - 1945"): "In early 1945, the First Polish Army, formed in the Soviet Union, and subordinated to the Soviet 1st Belorussian Front, reached Pomerania, the ancient land of the