Before revision: The Ħal Saflieni Hypogeum in Paola, Malta, is the oldest example of a prehistoric hypogeum, the earliest phase dating to 3600–3300 BC ; it .
After revision: The Ħal Saflieni Hypogeum in Paola, Malta, is the oldest example of a prehistoric hypogeum, the earliest phase dating to 3600–3300 BC .