From: Wikipedia. By A. Pegler. Mithraeum of Victorinus, Aquincum. From the west. 2008.
A Mithraeum II discovered at Altofen in 1888.
Kuzsinsky in BpR I, 1889, 59ff and plan; Ausgr. Aq., 8ff; Wolff in WsdZ 1894, 45ff; MMM II 321f. No. 213 and fig. 185; Kuzsinsky, Aquincum, 53ff and plan; BpTort., II, 584 fig. 26. See fig. 453.
The sanctuary is rectangular (L. 15.03 Br. 7.06) and is two mtrs. below actual
floor-level. One enters room A (L. 4.75 Br. 2.90) by
means of two or three steps; the adjoining room B(L.
0.85 Br. 2.90) is separated from A by a big wall. Through
a door (Br. l.25) one enters a pronaos (L. 5.90 Br.
3.00) and from here through a second door and by
means of two steps one enters the sanctuary proper
(L. 5.90 Br. 7.30). This is divided into a centre aisle
D (Br. 218) and the two benches EE (Br. l.60-l.80
H. 0.60) which are accessible by means of a step
next to the entrance. In the walls of the benches four
bases (H. 0.65 Br. 0.30) are walled in. The benches are
connected with the elevation for the cult-relief; before
it is a step between two bases (a, b).
The Wikipedia article claims that a tauroctony fragment was found. If so, this is not listed by Vermaseren in the CIMRM:
A fragment of the tauroctony (the main cult image) was found in the excavations and would have stood on the large stone base at the end (south) wall of the temple cella. ... The tauroctony fragment and the altar are located in the eastern wing of the Lapidarium situated at the northern edge of the Archaeological Park.