According to renowned psychiatrist Professor Körner, it was at Sonnenstein that “the idea of a purely psychiatric hospital” was realised. Sonnenstein’s good reputation was based upon its exceptionally humane, liberal and occupational-therapy-oriented complex treatment. Thanks to remarkable success achieved in healing, Sonnenstein gained attention and recognition throughout Germany and Europe.

The sanatorium had a sustainable influence on the development of German and European psychiatry, which led to a monopoly on the education of psychiatrists in the first decades of its existence. The successful work of Dr Pienitz was continued in following decades by head doctors Dr Friedrich H. Lessing, Dr Guido Weber and Dr Georg Ilberg.


A castle and fortress were built on the Sonnenstein in the 11th century, and continued to be used for military purposes until the 16th century. A well and a brewery were also built in the 16th century.

In 1811, the Sonnenstein psychiatric hospital was founded in the castle – Sonnenstein became the epitome of modern psychiatry.

At the end of the 1930s, the National Socialists took over the premises. On 9 October, 1939, Saxon Interior Minister Fritsch ordered that the Sonnenstein psychiatric hospital, which had already been partially cleared for use as a military hospital, be closed to the public.

At the beginning of the 1950s, the engineers from Junkers Aircraft Works and BMW that were taken prisoner by the Russians were brought to Sonnenstein to develop jet engine technology for the East German aviation sector.

Turbomachinery plant VEB was founded. After reunification, the company and the premises were privatised. When the factory closed at the end of 1994, the premises were gradually renovated and restored.

A number of buildings, including Sonnenstein Castle, were put to use for official purposes (district administration). Several new buildings were constructed (district court buildings); other authorities then followed (education authority, surveyor’s office), and a large clinic was built where the factory once stood.

A few years ago, the castle park and surrounding land became the property of Sonnenstein GmbH und Co. Naturprodukte KG, the company that rediscovered and tapped the healing spring that was renowned there many centuries before. Test drillings and samples attested to excellent water with superb laboratory findings; further testing found that it had an extraordinarily crystalline, hexagonal structure.

In 2016/17, a 19th-century building was renovated in the park near to the spring for the purpose of spring water production.