Beira is an international harbour, with connection to Zimbabwe, Zambia and other inland states. It has also an important fishing activity. The city of Beira is located in the central Mozambique, at approximately 19º 50’ S and 34º 50’E, in the northern margim of the Púngoe River mouth. The estuary is connected to a large bay, the Sofala Bay, which is freely and widely connected to the shelf, the Sofala Bank. Unlike most of the harbours, the Beira harbour is only 3-4 nautical miles distance away from the open sea. Hence there is no significant tidal phase lag between the tide gauge station and those observed in the adjoining sea. The Sofala Bay constitutes the southern part of the Sofala Bank. This region is the largest part of the shelf, about 80 nautical miles from the coast to the shelf break. The average depth of the shelf, in this region, is about 20 m.