University staff expecting to find nothing more than dustballs during a departmental cupboard clean out stumbled on royal food items from the Mesopotamian city of Ur in southern Iraq.
Researchers from the University of Bristol pulled a wooden box down from the top of a cupboard in the Department of Archaeology and Anthropology and found it was filled with ancient pottery, seeds and animals bones.
The goods were marked with words such as 'predynastic', 'sargonid' and 'Royal Tombs' written on index cards.
The team's investigation revealed that these were the remains of food offerings from a royal tomb at least 4,500 years old.
It is believed the remains were collected during famous excavations by Sir Leonard Wolley in the site of Ur in southern Iraq during the 1920s and 1930s, but staff had no idea the rare items were being stored at the university.
Experts described the discovery as particularly exciting due to the rarity of such environmental finds in this early period of archaeological fieldwork.
Dr Tamar Hodos, senior lecturer in Archaeology at the university said the remaining mystery was how the box had come to be left on top of the cupboard.
The remains will now join the rest of the British Museum's collection from Ur, which is part of a digitisation programme sponsored by the Leon Levy Foundation and undertaken with the University of Pennsylvania Museum.