Temple of Jupiter Anxur historical timeline

What a visitor stands in front of at Monte Sant'Angelo is a platform, not a temple. Of the great temple there is little more than the podium; of the terrace that carried it there are twelve arcades of Roman concrete, intact, which is why the monument reads from the Pontine plain two thousand years later. The sanctuary went through at least three phases -- a polygonal-masonry terracing of the late fourth century BC, a mid-second-century rebuilding against the rock, and a Sullan reconstruction that threw the whole thing out over the hillside -- and then became a monastery, a medieval fort, a ruin called Theodoric's palace, and since 2000 a natural monument.

Chronology

1. late 5th c. B.C. Rome takes the Volscian town of Anxur for good, on the southern slopes of the mountain. The oracular cult on the summit is, by the comune's reckoning, already some centuries old at this point.
2. 329 B.C. Terracina becomes a Roman colony, which puts the sanctuary inside the Roman system rather than facing it.
3. 312 B.C. The new Via Appia between Rome and Capua is routed round the back of the mountain, and the first terracings in polygonal masonry are built for a first monumental sanctuary -- probably tied to the oracle and probably with no temple in it. A stretch of that polygonal substructure still survives high on the terrace, towards the west.
4. c. 140 B.C. A rebuilding sets a series of rooms against the rock upslope -- the terrace now called the small temple. Its nine vaulted rooms keep stucco and painting imitating a marble revetment, First Style, of the third quarter of the second century BC, and they are the oldest decoration on the site.
5. 83 B.C. A barrier wall goes up north of the sanctuary across the Appian Way, probably in answer to Sulla marching on Rome during his struggle with Marius. The wall circuit and its nine round towers are what the upper terrace is.
6. early 1st c. B.C. The Sullan reconstruction. A military camp controls the Appian Way from the top, and the new great temple is raised on a scenographic foundation terrace in opus incertum with a portico behind it -- facing the port and the commercial traffic rather than the city and its farmland, which is a change of what the sanctuary was for. The twelve arches date from here.
7. 9th century A Benedictine monastery dedicated to San Michele Arcangelo settles in the small temple area, and the whole hill takes its present name from it. An internal substructure corridor is turned into the church, and its frescoes survive: a Madonna and Child between Saints Michael and Gabriel on the end wall, where the altar stood.
8. 1200s Military use of the summit continues -- the remains of a square tower, enclosure walls and traces of thirteenth-century occupation. The ruins are known through these centuries as the palace of Theodoric.
9. late 1500s The area is definitively abandoned as Terracina depopulates. It stays abandoned for three hundred years, which is why so much of the substructure is still standing.
10. 1894 The local scholar Pio Capponi makes the first excavations. The pit at the foot of the oracle rock gives up a great many lead votive offerings.
11. 1896 Luigi Borsari excavates further.
12. 1988 More of the monastery comes to light in the upper part of the terrace -- rooms with bases for presses and basins, which is the monks' working side rather than their church.
13. 2000 The Temple of Jupiter Anxur is protected as a natural monument and entrusted to the Comune di Terracina, which still manages it. The Fondazione Città di Terracina runs the site, open daily at 7 euros.

Survival and restoration

This building was wrecked once and then left alone, and the second part is why it survives. After the Roman period the sanctuary was destroyed and burnt. The cella shows a repair that may predate even that: it was originally wider inside and was later lined with a reinforcing wall, possibly after a fire. From the late sixteenth century, when Terracina emptied out, nobody had a use for the summit at all.

What did reuse it, reused it carefully by accident. The Benedictines of San Michele Arcangelo took the small temple's internal corridor and made a church of it rather than clearing the site, which is how a ninth-century fresco came to be preserved inside a second-century BC substructure. Medieval military builders added a square tower and enclosure walls on the summit. The vaulted corridor behind the small temple's nine rooms has partly collapsed since.

The dedication is the thing that has not survived. The traditional identification is Iuppiter Anxur -- Jupiter as a boy -- but an inscription naming Venus was found on the site, together with votive objects including glass-paste doves inscribed to Venus Obsequens, and the comune's own portal treats the female-deity hypothesis as open. The smaller and probably older sanctuary has recently been attributed to Feronia, a cult perhaps brought into the region under the Volscian occupation in the fifth century BC and attested elsewhere in the city, where ancient sources record a fanum Feroniae near Monte Leano. Three candidates; one of them is in the monument's name.

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