The foundations of a 12th century prayer hall have been discovered under the Al-Nuri mosque in the Iraqi city of Mosul.
That is where ISIS once proclaimed their headquarters.
The mosque and its iconic leaning minaret were severely damaged by ISIS during a battle in 2017, and had been undergoing reconstruction.
Four additional rooms for the performance of Wudu or ablutions were also discovered under the prayer room, excavators said.
The excavation was carried out by the department of antiquities and heritage in Iraq’s Nineveh province, with support from UNESCO and funding from the United Arab Emirates.