Ceuta Cathedral

The Cathedral of St Mary of the Assumption is a Roman Catholic church located in the Spanish city of Ceuta, in a small exclave on the northwest coast of Africa.

A primitive Eastern Roman Christian church stood on the site, and some researchers have identified this with the one built in the 6th century by Emperor Justinian I. This was replaced by the old Great Mosque of Ceuta, an architectural work of enormous wealth, according to descriptions which have survived, and although it underwent several enlargements, hardly any remains of it are to be seen today.

After the Portuguese conquest of 1415, the Great Mosque was transformed into a Christian church by alterations, but there is no record of what they were.

Source: Wikipedia