The location of the Temple of Jupiter Stator remains in question. However, many scholars believe that the remains of the Temple of Jupiter Stator consist of the platform of peperino and travertine blocks just southeast of the Arch of Titus. Ann Vasaly refers to a catalogue of the city of Rome from the 4th century C.E., the Itinerarium, which suggests that the temple stood at the head of the Sacra Via next to the Temple of Venus and Roma. Additionally, she mentions Ovid's reference to the Temple of Jupiter Stator from his Tristia (3.1 31-32) which states that the temple lies on the right side of the Sacra Via as one walks up it.
Source:According to tradition, the temple's origin dates back to Romulus' construction of a small shrine near the Porta Vetus (Porta Mugonia). According to Livy (I.xii 3-6), Romulus had vowed such a monument during a critical moment in battle against Sabine forces who had swept the Romans from the Forum area back to the city gates. The epithet "Stator" seems to mean "stayer" - derived from the subsequent successful stand made by the Roman forces at that spot.
The first true "temple" or "aedes" was built in 294 BCE by M. Attilius Regulus who dedicated a temple on the spot - in reaction to a similar vow made during the Samnite Wars. The current remains, a platform of peperino and travertine, date to the Flavian period.
Richardson (1992) notes that the foundations suggest a prostyle and hexastyle structure with a deep pronaos and squarish cella. Platner and Ashby cite its presence in a relief from the Tomb of the Haterii (in the Vatican Museum's Lateran holdings) which shows a hexastyle temple in the Corinthian order.
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