Where does Hannah travel back in time to?

In the novel, Hannah travels back in time to 1942, to a village near the city of Lublin in what is now Poland. Her name was Chayah. Her aunt and uncle have taken her in because her parents died of an epidemic illness in Lublin, where they lived.
Soon she and her relatives are taken to a so-called work camp. The Nazis operated numerous, infamous concentration camps in Poland, including Majdanek and Treblinka. The camp where Hannah/ Chayah and her family go is almost certainly Auschwitz. This is indicated by the now well known sign over the front gate, which read in German, "Arbeit macht frei," which means "Work makes you free." As many Jews had been sent to hard labor and knowledge of the mass murders was suppressed, many captives believed this was actually a work camp.