What is "gesiowka"

Gęsiówka is the colloquial Polish name for a prison that once existed on Gęsia ("Goose") Street in Warsaw, Poland, and which, under German occupation during World War II, became a Nazi concentration camp.

In 1945–56 the Gęsiówka served as a prison and labor camp, operated first by the Soviet NKVD, then by the Polish communist secret police.