The Mummy Grotto is part of the Christiansen Park in Flensburg, which was commissioned by the merchant Peter Clausen Stuhr.
The Mummy Grotto was created around 1800 during Stuhr's lifetime. It houses a human-shaped Phoenician sarcophagus dating from around 400 or 360 BC.
The sarcophagus was placed in the landscape garden and then covered with a rock grotto. Its origin is unclear; it may have come to Flensburg by chance as ballast.