Wikipedia
The Umschlagplatz was the square in Warsaw under German occupation, where Jews were gathered for deportation from the Warsaw Ghetto to the Treblinka extermination camp as part of Operation Reinhard during the Holocaust in Poland. A monument was erected in 1988 on Stawki Street, where the Umschlagplatz was located, to commemorate the deportation victims.
During the Grossaktion Warsaw, which began on 22 July 1942, Jews were deported in crowded freight cars to Treblinka. On some days as many as 10,000 Jews were deported. An estimated 300,000 Jews were taken to the Treblinka gas chambers; some sources describe it as the largest killing of a community in World War II. The mass deportation action ended on 21 September 1942, although trains to Treblinka continued to depart until the end of the Warsaw Ghetto Uprising in 1943.
The Umschlagplatz was created by fencing off a western part of the Warszawa Gdańska freight train station that was adjacent to the ghetto. The area was surrounded by a wooden fence, later replaced by a concrete wall. Railway buildings and installations on the site, as well as a former homeless shelter and a hospital were converted into a prisoner selection facility. The rest of the train station served its normal function for the rest of the city during the deportations.