Chełmno extermination camp

, known for =
, location = Near Chełmno nad Nerem, ''Reichsgau Wartheland'' (German-occupied Poland)
, built by =
, operated by =
, commandant = Herbert Lange, Christian Wirth
, original use =
, construction =
, in operation = – (1st period),
–
, gas chambers = 3 gas vans
, prisoner type= mostly Jews
, inmates =
, killed = est. 152,000–200,000
, liberated by = Red Army,
, notable inmates = Mordechaï Podchlebnik, Szymon Srebrnik, Szlama Ber Winer
, notable books =
, website =

Chełmno or Kulmhof was the first of Nazi Germany's extermination camps and was situated north of Łódź, near the village of Chełmno nad Nerem. Following the invasion of Poland in 1939, Germany annexed the area into the new territory of Reichsgau Wartheland. The camp, which was specifically intended for no other purpose than mass murder, operated from , to , parallel to Operation Reinhard during the deadliest phase of the Holocaust, and again from , to , during the Soviet counter-offensive. In 1943, modifications were made to the camp's killing methods as the reception building had already been dismantled.

At the very minimum, 152,000 people were murdered in the camp, which would make it the fifth deadliest extermination camp, after Auschwitz, Treblinka, Bełżec, and Sobibór. However, the West German prosecution, citing Nazi figures during the Chełmno trials of 1962–65, laid charges for at least 180,000 victims. The Polish official estimates, in the early postwar period, have suggested much higher numbers, up to a total of 340,000 men, women, and children. The gives the figure of around 200,000, the vast majority of whom were Jews of west-central Poland, along with Romani people from the region, as well as foreign Jews from Hungary, Bohemia and Moravia, Germany, Luxembourg, and Austria transported to Chełmno via the Łódź Ghetto, on top of the Soviet prisoners of war. The victims were murdered using gas vans. Chełmno was a place of early experimentation in the development of the Nazi extermination programme.

Red Army troops captured the town of Chełmno on . By then, the Germans had already destroyed evidence of the camp's existence, leaving no prisoners behind. One of the camp survivors, who was fifteen years old at the time, testified that only three Jewish males had escaped successfully. The ''Holocaust Encyclopedia'' counted seven Jews who escaped; among them was the author of the Grojanowski Report, written under an assumed name by Szlama Ber Winer, a prisoner in the Jewish '' Sonderkommando'' who escaped only to perish at Bełżec during the liquidation of yet another Jewish ghetto in German-occupied Poland. In June 1945, two survivors testified at the trial of camp personnel in Łódź. The three best-known survivors testified about Chełmno at the 1961 trial of Adolf Eichmann