Opposite the entrance to the main ruins is the exquisite Temple of Venus, which preserves a section of a circular building with fluted columns. During the early Christian era, this was turned into a basilica and dedicated to St Barbara (who joined the saintly ranks when her pagan father tried to kill her for converting to Christianity – he got his comeuppance when a bolt of lightning reduced him to a smouldering heap). Next to it is a fragmentary Temple of the Muses.
This temple area wasn't open to the public at time of last visit, but is easily admired from the pavement around it.