The two men were searching for mushrooms in Rüsselheim, near Frankfurt am Main, when they made the find.
Police were called and a further search discovered human bones apparently belonging to the skull.
All the bones were taken away for further examination and there is no indication yet of the person’s age, gender or identity.
Investigations are continuing. "We hope to identify the person by the end of this or the start of next week," a police spokesman told The Local. "It will take a little while."
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