Originally an Anatolian mother goddess, the cult of Cybele was formally brought to Rome during the Second Punic War (218 to 201 BCE) after a consultation with the Sibylline Books.
[4] Annually, on 27 March, the sacred black stone of the Magna Mater was brought from her temple on the Palatine to where the brook of the Almo (now called the Acquataccio) crossed the via Appia south of the Porta Capena, for the ceremony of "Lavatio" (washing).
Although there are numerous references to this ceremony, it seems to have constituted a "locus sacratus" or sacred place rather than a permanent building, in view of the lack of archaeological evidence for it.
[citation needed] A tholos, adorned with frescoes, is at the top of the Sacra via, where the Clivus Palatinus branched off to the south.
A shrine was located on the right bank of the River Tiber, near the racecourse of Caligula (Gaianum), known from several inscriptions on fragmentary marble altars,[9] dating from 305 to 390 CE, all but one of which were found under the façade of S. Peter's in 1609.