The oldest graduation tower in Poland is located in Ciechocinek and was built in 1806 on the advice of Stanisław Staszic. It was originally built as a technological, salt-manufacturing installation for use in the process of increasing the density of saline waters from which the salt used for consumption and therapeutic purposes was obtained. Before long, people noticed that the atmosphere around the graduation tower was saturated with a saline aerosol. It was then that the tower was first put to use for therapeutic purposes. Technological progress meant that it lost significance as salt-manufacturing equipment. However, its role as a sanatorium facility rose in its stead. The graduation towers constructed nowadays are designed for health resort purposes.
The Ciechocinek graduation tower uses saline waters at a concentration of 5.6 per cent and they contain iodine and a negligble admixture of hydrogen sulphide. Its entire structure is wooden. There are two channels running from top to bottom and the saline water is pumped into them via a pipeline. The whole scaffolding framework is filled with blackthorn branches. The saline water flows through the channels, becoming more and more concentrated as it does so. Thus prepared, it then flows into the salt works. As it runs through the channels, the saline water is reduced to fine droplets. The sun, the wind and the temperature all act on them and this leads to the creation of aerosol particles.