The former Nazi death camp of Auschwitz-Birkenau was closed to visitors on Monday as torrential rain sparked a flood alert across southern Poland, the museum at the site said.
Jaroslaw Mensfelt, spokesman for the state-run Auschwitz-Birkenau Memorial and Museum, said staff were also scrambling as flood waters swelled the nearby River Sola.
"The archives, documents and all the materials at ground level are currently being taken up to the next floor," Mr Mensfelt told AFP. "We started the operation after local authorities issued a flood alert," he said. "Everyone who's able to carry something has been mobilized," he added, noting that the museum's entire 250-strong staff was involved.
The River Sola runs a few hundred meters (yards) from Auschwitz, the site of the original camp set up in 1940 by Poland's German occupiers in the southern Polish city of Oscwiecim.
Besides the archives, the section houses displays on its history and the museum administration, in a former Polish army base that the Nazis transformed into a camp a year after the start of World War II.
The Nazis opened the notorious, purpose-built Birkenau camp nearby in 1942. One million of the six million Jews who perished in the Holocaust were murdered in Auschwitz-Birkenau, mostly in its gas chambers, as well as tens of thousands of others including Poles, Roma and Soviet prisoners of war.