The Temple is dated from the decade 30 to 20 BC. It was part of an ancient agglomeration composed of dwellings, thermal baths and farm buildings. It is placed in the center of a semi-circular peribole, facing a spring which was undoubtedly the founding element of this monument. These remains make it possible to represent its original state fairly accurately.
A tetrastyle Corinthian temple, it was comprised of two rows of columns, four in front and two in back; one of which is still visible today. Behind was the cella or worship hall, framed by pilasters at the four corners. In front, between two protrusions of the podium, a staircase allowed access to the temple and some of these steps were still preserved in the 16th century. This temple belongs to the first generation of Corinthian temples which preceded in particular the Maison Carrée of Nimes. The small column that can be seen above the chapel is most likely part of an opening made in the wall during the Merovingian or Carolingian period during a probable re-use of the building as a church.
Classified as a Historical Monument, the temple was probably dedicated to a cult deity of water since a spring is nearby. It is also called Roman Temple Low Castle or House-Lower Temple. The first list of Historical Monuments was created in 1840 and included 1034 monuments, including Chateau Bas.
Of the three ancient French temples still existing in France, it is the only one found in the countryside. This picturesque setting makes this place one of the most romantic landscapes in the region.