The train was organized during the deportations to Auschwitz in May–July 1944 of 437,000 Hungarian Jews, three-quarters of whom were sent to the gas chambers. Its passengers were chosen from a wide range of social classes, and included around 273 children, many of them orphaned. The wealthiest 150 passengers paid $1,500 () each to cover their own and the others' escape. After a journey of several weeks, including a diversion to the Bergen-Belsen concentration camp in Germany, 1,670 surviving passengers reached Switzerland in August and December 1944.