Secretary-General of the United Nations Ban Ki-moon (R) walks with former prisoner of Auschwitz Marian Turski, during a visit to the former Auschwitz concentration camp on November 18, 2013 in Oswiecim, Poland. (BARTOSZ SIEDLIK/AFP/Getty Images)

United Nations Secretary-General Ban Ki-moon, in Poland for a UN climate conference this week, visited Auschwitz, the notorious Nazi concentration camp in Oswiecim, Poland. Ban is the second UN secretary-general to visit Auschwitz—the first was Boutros Boutros-Ghali, who toured the concentration camp in 1995.

Ban met with Yisrael Meir Lau, the former chief rabbi of Israel and current Yad Vashem chairman whose son, David Lau, is currently chief rabbi, and gave brief remarks. “I stand in disbelief before the gas chambers and crematorium—and shudder at the cruelty of those who designed this death factory,” Ban said.

“The world must never forget, deny or downplay the Holocaust,” Ban added. “We will stand in eternal solidarity with the survivors and safeguard their testimony so their legacy will never die.”

Ban’s message was one of hope as well: “Auschwitz-Birkenau is not simply a register of atrocities. It is also a repository of courage and hope. Today I say loud and clear: Never again.”

The Secretary-General also visited the Chevra Lomdei Mishnayot synagogue in Oswiecim, which is maintained by the Auschwitz Jewish Center, before heading to Krakow.