At Sutri (Sitrium), in the same rocky hill in which the Roman Theatre has been built, there is the Madonna del Parto's church. From its structure it becomes clear, that this originally must have been a Mithraeum.The present atrium of the church certainly served for a pronaos in the original Mithraeum. By it one enters the proper, orientated sanctuary (L. 21.20 Br. 6.70), which is sparsely illuminated by three windows in the leftside-wall. Two rows of ten columns, resting on one uninterrupted base, support the vault above the central aisle (Br. 2.47). The side-aisles however, have flat roofs.The sanctuary has thus the usual division into a central aisle and two side-benches, the construction of which are still easily discernable. For there are two elevations (H. 0.50 Br. 0.30) running along the bases of the columns an two other elevations run along the side-walls. There is nowadays a narrow corridor (Br. 0.75) along side the latter elevations and the bases of the columns; but they certainly formed one whole.The floor of the central aisle slopes upwards to the choir, broadening considerably and beginning at the end of the podia. In the back-wall there is a niche with a fresco of the H. Virgin but which originately must have contained the relief of Mithras tauroctone. This niche is accessible via three steps. Remarkable is that in the elevation a square basin is still visible. A brook, running in the immediate vicinity, supplied it with the required water.