PRAGUE (AP) — A new memorial opened on Tuesday in the Czech Republic on the site of a former Nazi concentration camp for Roma, after a communist-era pig farm was removed.

The official opening capped a process that took decades and was made possible after the Czech government agreed to remove the farm.

“It’s very positive news for me that the whole project was completed,” said Jana Horvathova, the director of the Museum of Romani Culture, whose organization is in charge of the memorial.

Roma and human rights activists had long demanded the removal of the farm from Lety, 60 miles (95 kilometers) south of Prague, where some 1,300 Czech Roma were sent between August 1942 and August 1943 during the Nazi occupation of what was then Czechoslovakia in World War II.

At least 335 people died there, according to the latest research, the museum said, while most of the others were taken to the Nazis’ Auschwitz death camp.