On the left side of the front of the enclosure, there is a panel depicting the myth of the foundation of Rome: Romulus and Remus are suckled by the she-wolf in the presence of Faustulus, the shepherd who adopted and raised the twins, and Mars, the god who generated them by joining with the vestal Rea Silvia.
At the center of the composition is the ruminal fig tree, under which the twins were suckled. On the tree one can recognize the claws of a bird, in 1938 completed like an eagle, but perhaps a woodpecker that, like the she-wolf, is sacred to Mars.
The god is represented in his warrior clothes, equipped with spear, helmet with crest adorned with a griffin and armor on which stands out the head of a Gorgon.
On the right of the front of the enclosure is visible the relief that depicts Aeneas, already elderly, in the act of making a sacrifice to the Penates and therefore is portrayed in priestly garb with his head covered, in the moment of making an offering on a rustic altar. The final part of the right arm has been lost, but it almost certainly held a patera, a ritual cup, as is suggested by the presence of a young ritual assistant (camillus) carrying a tray with fruit and bread and a pitcher in his right hand.
A second assistant to the ritual pushes a sow towards the sacrifice, probably on the very place where the city of Lavinium will be founded if we interpret the scene according to the 8th book of the Aeneid. Recently it has been hypothesized that the personage sacrificing is Numa Pompilius, the second of the seven kings of Rome, who in the Campo Martius celebrated a sacrifice to the concord between Sabines and Romans, on the occasion of which a sow was sacrificed.