The Sonnenstein Euthanasia Clinic (German: NS-Tötungsanstalt Sonnenstein; literally "National Socialist Killing Centre Sonnenstein") was a Nazi killing centre located in the former fortress of Sonnenstein Castle near Pirna in eastern Germany, where a hospital had been established in 1811.
In 1940 and 1941, the facility was used by the Nazis to murder around 15,000 people under the euphemism of "euthanasia".[1] The majority of victims had psychological disorders or intellectual disabilities, but their number also included inmates from the concentration camps.[1] Sonnenstein was one of six killing centres set up after the beginning of the Second World War as part of a nationwide, centrally coordinated and largely secret programme called Aktion T4 for the "elimination of life unworthy of life" (Vernichtung lebensunwerten Lebens) or the murder of what the Nazis called "dead weight existences" (Ballastexistenzen).
These murders at Sonnenstein and elsewhere served as organizational and technical preparation for the Holocaust; many of the key personnel of Aktion T4 had prominent roles in Operation Reinhard.[2] The method of murdering prisoners with gas was adopted at Auschwitz and other extermination camps.
Today, the Pirna Sonnenstein Memorial Site commemorates the victims of these crimes.