When the Greeks came here, at the same time or immediately after the foundation of the city, they founded an important sanctuary dedicated to the goddess Hera, an important divinity especially in the Peloponnese where she is venerated and where the settlers of Sibari also come from then they will found Posidonia.
The Heraion or Temple of Hera Argiva was originally located at the mouth of the river Sele. The sanctuary is now about 1.5 km from the sea, for the deposit of alluvial soil carried by the river Sele.
Was an octastyle temple with 17 columns on the long sides. The stereobyte is presevered to its original height in some places. Following Ionic usage, the axes of the cella walls are alligned with those of the corresponding columns of the peristasis. A pronoas, noas, and adyton compose the cella, and the lateral walls had columns instead of antae. The pteroma widens greatly on the east side, equaling the dimensions of the three interaxials.
Unstable terrain dictated the placement of four courses under the peristasis and two under the cella.The columns are sandstone conglomerate, all with eighteen flutes, to which correspond two groups of capitals, diverse in profile. A multiple molding crowned the architrave and the moldings of the external face bear plastic decoration composed of Lesbian leaves, egg and dart, and bead and reel. Multiple molding bearing, from top to bottom, a Lesbian leaf, an Ionic leaf, and a small cyma reversa formed the normal Doric gesion above the frieze. The temple was entered by means of a ramp abutting the crepidoma on the east front and the altar is situated 34.1 m from this front.
The temple was erected towards the end of the 6th century BC. An earthquake, perhaps in 63 AD, probably destroyed the temple. The eruption of Vesuvius in 79 AD buried the Heraion complex and by the 4th century AD all traces of activity have disppeared.
In the Narrante museum, a very beautiful museum with an educational approach for schools and families, this essential part of the history of Paestum is explained.
And just recently have done multispectral studies on the metopes that come from this sanctuary, and today they are in the Paestum museum, which date back to the first half of the 6th century BC, therefore to the first or second generation of the city, probably founded around 600 BC.
According to these recent analyses, they were painted: therefore the long discussion whether these metopes were ever part of a temple or just a project begun and then abandoned can now be closed because if the metopes were painted, it means that they were also mounted on a building. And so somewhere here there must have been this first temple of Hera at the mouth of the Sele. It was probably right under the larger, more recent temple, which can still be seen in its foundation.