The new archaeological investigations on the so-called temple of Iuppiter Invictus on the clivus Palatinus, concentrated on the area west of the temple podium and, in two sectors a short distance from it.

The trench along the western side of the podium revealed interventions post-dating P. Rosa’s excavations which began in 1866. At the centre of the area being investigated a large circular pit with a diameter of 1.30 m emerged, which had been filled with ancient (marble mouldings, lumps of mosaic) and modern (bricks, wall tiles, plastic, fragments of perforated bricks) material, as well as marble and tufa chippings and stones. During the removal of the fill a large block of tufa was found incorporated into the cement of the podium, at a depth of 1.40 m below the floor level. The block was squared and present housings for tenons. The block rested on another cement layer, and had clearly been reused as the side with the tenon housings was visible instead of being on the top so as to be able to interlock with the next block. At a short distance from the block a small access (a narrow opening 30 cm in diameter) to a cavity below the podium was identified. The cavity had not been documented previously. The photographs taken inside the cavity showed how the stone quarry had been filled with a great quantity of earth and that this continued to the east, below the podium itself, whilst to the west the structure rested on natural.

Further excavation was undertaken at circa 25 m west of the temple around a large parallelepiped block of cement conglomerate made up of alternating bands of basalt, brick and travertine, resting on a large platform of tufa chippings. The block was leaning to the east, in the direction of another tufa quarry situated at a short distance away. The west side presented a brick stamp incorporated into the wall which read:

[—-]P(?)R AVRELI C(?)[—-], or [EX] PR(AEDIS) AVRELI C[AES]

The text can be interpreted in two ways: CIL XV 401 and CIL XV 719; both are stamps of Marcus Aurelius and Faustina, datable to between 155 and 161 A.D., before the death of Antoninus Pius.

The final intervention involved the sector to the south of the temple in the direction of the Domus Flavia. In a section of the new trench a moderate quantity of basoli from road paving were intercepted suggesting the existence of a road passing in front of the Romulean Walls already excavated by Rosa in 1867 and which ran along this part of the hill. This hypothesis will have to be tested by the continuation of excavations in the future.