Four basilicas have been identified and partially excavated within the early Christian walls.
Basilica B of Alkisson, the cathedral of Nicopolis, is located in the northeastern part of the city, dating back to the mid of the 5th century.
It is a large five-aisled basilica with auxiliary outbuildings to the southwest and elongated monumental portico at the western part. In the middle of the central nave fragments of the pulpit are preserved.
A characteristic feature of the interior decoration of the basilica are the architectural reliefs, a large proportion of which are spolia of Roman monuments.
The floors were decorated with marble pieces of various designs, while mosaics decorated the narthex, the three-arcade atrium and the outbuildings.
