Parts of a three-aisled early Christian basilica with a portico in front to the south were excavated on the southern slope of Keber Tepe in 2015 and 2019. The further uncovering of this was the focus of the work in 2020. Three sections were made to completely excavate the apse and the apse side rooms. Another section was used to further explore the buildings adjoining the church to the east, which had already been investigated in 2018 and 2019.

The Apse

The apse was completely uncovered. In the process, it was possible to further refine the phasing developed in the previous year. In the first phase, which dates to the later 4th century AD, the nave and sanctuary were separated by a threshold. The area of the sanctuary in front of the apse was covered with a mosaic floor that ended at the transition to the apse. How the apse itself was designed in this phase is largely unclear. As the mosaic ends at an excavation pit in the east, the apse appears to have been raised or separated by a step. However, it is not possible to draw precise conclusions about the design of the apse due to the later remodelling.

In a second phase (around 400?), the area of the sanctuary in front of the apse was raised by laying large limestone slabs on top of the mosaic. They have a continuous groove in the west, which served as an opening for barriers and separated the sanctuary from the nave. There is only a passageway in the centre axis. There is also no evidence of the design of the apse for this phase.

In a third phase 3 (5th/6th century), the sanctuary was completely remodelled. The apse was raised considerably and was now 0.7 metres above the floor of the central nave. It was decorated with a mosaic depicting a Nilotic scene framed by various ornamental bands. Doors led from the apse into the northern and southern apse side rooms.

The apse could be reached from the central nave via a staircase built from spolia in the centre axis of the church. The areas of the sanctuary around the staircase were also raised to the height of the apse mosaic and covered with reused marble slabs, but not across the entire width of the room, only in the extension of the apse to the west. The area of the sanctuary was thus reduced.

At an unknown point in time, extensive destruction occurred, followed by makeshift repairs. This fourth phase can be seen above all in the north-west of the sanctuary. In the area between the wall to the side aisle and the raised platform in front of the apse, which was added in phase 3, there were dozens of marble slabs, some of them large, which had apparently fallen from the walls. Among the heterogeneous, but often matching fragments, there are also high-quality Champlevé reliefs, as they are mainly known from northern Syria and Cyprus. Some of the painting is still preserved. The slabs are obviously still lying in a cambered position. Instead of removing them, the area was walled up and separated from the nave.

North aisle and apse side room

In the north, the eastern end of the side aisle was completely uncovered. The floor is decorated with a mosaic floor showing intertwined multiple meanders that enclose square fields with geometric patterns. Above the mosaic floor, the horizon of destruction already recorded the previous year continued. In addition to many hundreds of roof tile fragments, numerous fragments of glass lamps and window glass were found here. It was possible to trace a water pipe that was subsequently laid through the mosaic floor. It comes from the northern apse side room, which is accessible through a narrow doorway in the eastern boundary wall of the side aisle.

Contrary to expectations, it appears that the apse side room does not belong to the first construction phase of the church. This is indicated above all by the northern outer wall, which differs in orientation and character from the outer wall in the area of the northern side aisle. On the one hand, it leans clearly to the south and is slightly curved, and on the other, the ashlars are less carefully offset. The roughly worked, sloping rock serves as the floor, with rammed earth also used in some areas. There is no evidence of a mosaic floor. Three open stone boxes, which could be simple reliquaries, are lined up in front of the north wall.

Beyond the northern outer wall of the apse side room, three sewage pipes were found running parallel to each other in a flat curve at different levels from north-west to south-east. They are clearly located above the church and must refer to buildings, perhaps a road, located above on the slope.

The southern side room of the apse

The southern apse side room was also completely uncovered. It is significantly wider than the southern aisle and is covered with a simple mosaic of large white tesserae. Surprisingly, the room is not rectangular. The southern boundary wall runs at a recognisably obtuse angle to the west. Like the mosaic, it breaks off to the south, so that it remains unclear how the transition to the side aisle was designed. All that has survived is a simple pillar pedestal, which stands exactly in line with the wall between the northern aisle and the northern apse side room and apparently marks the transition to the southern aisle. Compared to the mosaics of the central nave and the side aisles, the mosaic of the southern apse side room is very simple. It is likely that it was added in a late remodelling phase or that the entire room was created at a later date. No remnants of the room’s other furnishings and fittings have survived, meaning that its exact function can no longer be determined.

Neighbouring buildings east of the church

During the excavations in 2018 and 2019, parts of a large room with a simple mosaic floor were uncovered to the east of the church. To the north, it bordered a narrow corridor lined by a colonnade made of spolia. These structures could be further analysed in the sections. This revealed that they were directly connected to the church. The room with the mosaic adjoins the south-east corner of the apse side room. The two rooms are not directly connected, but the mosaic floors are so similar that they must have been laid at the same time. The adjoining corridor not only runs against the rear wall of the southern apse side room, but is also connected to it by a subsequently installed threshold. The column position to the north of the corridor also abuts the rear wall of the basilica. A total of four bases have now been uncovered. Further to the north is a pavement of limestone slabs of varying sizes. This paving is possibly directly connected to a paving that adjoins the outer wall of the basilica. Another column position was also discovered there. Overall, it is clear that the entire area to the east of the church was densely built-up. However, it is not yet possible to say what function these buildings had and how they were dated.