This article focuses on the large quadripartite church complex in the north-eastern part of the settlement on the Burgbichl. The church is orientated towards a two-storey residential building to the west and is connected to it by a narrow narthex. In the main room, the presbytery is separated from the lay room by a step that once supported the partition and has a passageway in the north. The relationship between the two sections is particularly striking, as the area for the priesthood is very large. To the east of the main hall, a sacristy with T-shaped underfloor heating offers a high level of comfort. For the side chapel to the south a change of function can be traced clearly: It initially served as a baptistery with a hexagonal basin and is then transformed to a memoria.
Both to the north and south of the church wings of rooms are adjoined, which probably cannot be explained solely by liturgi-cal purposes. The wing in the south is remarkable for its two storeys and its vaulted ceiling in the staircase. In the north, it has been proven that an enclosure wall was built in the latest phase of the settlement, for which parts of the church building had to be removed. According to the current state of research, the entire building complex in Irschen represents a quite unique architectural feature that most likely only shares a parallel to Ajdna nad Potoki (Slovenia).