As opposed to the round Temple of Hercules the neighboring Temple of Portunus was erected on a plan of a rectangle and situated on a high podium with wide stairs leading to a broad vestibule (portico) adorned by columns with Ionian capitols. Further on there was a sanctuary (cell), whose walls were decorated with semi-columns with similarly fluted shafts and Ionian heads. In the cell there was a statue of Portunus, to whom Romans prayed to beg for his favors, meaning a lack of floods which would damage the harvests and the city and a stable level of water on the Tiber, which guaranteed sailing without any difficulty.

As can be seen the temple was preserved in an excellent condition, despite the fact that it is one of the oldest ancient structures in Rome. The original building which was erected in this location dates back to IV century B.C. It was modernized two centuries later and in this condition it remained until early Middle Ages. The fact that later it was not used as building material is due to, as was often the case at that time, changing of its patron – from a pagan one to Christian. In the IX century the temple was given a dedication to Santa Maria in Secundiciero, which was a reference to the function of its protector at that time, Stefano Stefaneschi – secundicerius, meaning a vice-chancellor in the Apostolic Chancery. At that time the column vestibule was walled up, creating uniform internal space which was decorated with medieval frescoes. At the end of the XV century Mary of Egypt became its new patron – a hermit repenting for her sins and the intercessor of women of questionable reputation, who in this location of the former Roman port situated in the area of an enormous, ancient brothel, found their intercessor. The story of Mary of Egypt – a fallen woman, who thanks to divine intervention set off on a path to sainthood, fit very well with a legend alive in Roman ancient tradition about another famous prostitute. This was Larentia, with whom Hercules had spent the night during his stay in Rome prior to returning to Greece. At the behest of the hero, Larentia became interested in the first man she encountered after that night. This was the old, but wealthy Tarrutius, who accepted the fallen woman into his household, while after his death left her a great fortune. She on the other hand, after her death, left everything she had to the Roman populace. That is why her tomb, found near Forum Boarium in the Velabrum district was venerated in a special way in the form of annual sacrifices.

In the XVI century, the deteriorating church was given over the Armenians inhabiting Rome, who added a hospice to it, designated for pilgrims arriving from Armenia. Another, this time pagan unveiling of the building took place in the twenties of the XX century during the time of Benito Mussolini, when the church was shut down. This was one of the numerous places reminding of the ancient tradition of Rome of which Duce desired to be the protector, even continuator. The buildings of the old hospice were destroyed, while the furnishing of the Church of Mary of Egypt were transferred to another church – the San Nicola da Tolentino, where the national church of the Armenians also found its new residence. And thus history had run full circle. Today the ancient, restored temple can be viewed accompanied by the noise of cars from the nearby, busy via Luigi Petroselli. Very few people pay attention to it, while tourists exhausted from waiting in long lines to the tourist mecca known as the Mouth of Truth (the vestibule of the Church of Santa Maria in Cosmedin) pass by it without a second thought (and perhaps it is for the better), despite the fact that today, after years of conservation work it can be accessed (on the first and third Sunday of the month, with prior reservation via the telephone) and move back in time thousands of years, to the beginnings of the city on the Tiber, with which it had always been inseparably connected.