The Temple of Hercules Victor is a very ancient building located in Rome's Forum Boarium.  It is a round temple surrounded by colonnades on all sides.  The building dates from the late 2nd Century BC.  The original wall of the cella and all but one of the original columns remain, making this the oldest, surviving marble building in Rome.  The round design of this temple caused it to be mistaken for a Temple of Vesta for many years.

The Temple of Portunus is another ancient building in the Forum Boarium, dating from 100 BC.  This rectangular building consists of a portico and cella raised on a podium, reached by a flight of steps.  The columns of the portico are free-standing, while the columns on the sides and the rear are recessed into the walls of the cella.  All these elements of the original building remain.   This temple owes its state of preservation from being converted to use as a church in 872. 

The Forum Boarium was the cattle forum of Ancient Rome and is the oldest forum in Rome.  It was located next to premier port of Rome and experienced intense commercial activity.  In addition, the Forum Boarium was the site of the first gladiatorial contest, which took place in 264 BC. The Forum was also a religious center.

Today, across the street from the forum is the Church of Santa Maria in Cosmedin, famous for its Bocca della Verita (Mouth of Truth sculpture).