The Auschwitz-Birkenau State Museum says conservation work has been completed on half of a wooden barracks that housed prisoners at the former Nazi German death camp during World War II.

The restored half had been on loan to the United States Holocaust Memorial Museum in Washington, D.C., for more than 20 years before it was returned in 2013 to its original site in southern Poland, under German occupation during the war.

A spokesman for the Auschwitz museum, Pawel Sawicki, said Tuesday that conservation work on the half that was returned from the U.S. was completed in mid-July and it will open to study groups in August, following a gathering this week of Catholic youth in the area with Pope Francis.

The part that remained on the site was previously restored.