Complex sentence: During World War II the area was part of the German Gothic Line: in April 1945, in the Allied advance of Operation Roast's, it was the location of the Battle of the Argenta Gap.
Split into simpler sentences: During World War II the area was part of the German Gothic Line. In April 1945, in the Allied advance of Operation Roast's, it was the location of the Battle of the Argenta Gap.