The measurements made during the last 50 years and the salinity increase of the Baltic are described. The transport of bottom water between the basins, the salt inflows and the stagnation periods are discussed. The great salt inflow of 1952 and the long stagnation which followed it are described in detail. The conditions during 1960 and the turnover of the water in the Gotland basin in 1961 are discussed and described. The accumulation of nutrient salts in the Gotland basin during the stagnation is described and the conditions are compared to other anoxic basins. The analysis method for hydrogen sulphide is described. The development of the stagnation in the Gotland basin is traced in detail. The speed of the inflow is discussed.