SACER MONS
SACER MONS (τοἻερὸν ὄρος) was the name given to a hill about 3 miles from Rome, across the Anio and on the right of the Via Nomentana. It is mentioned only on occasion of the two secessions of the plebeians from Rome: the first of which, in B.C. 494, was terminated by the dexterity of Menenius Agrippa, and gave occasion to the election of the first tribunes of the people. (Liv. 2.32; Dionys, 6.45; Appian, App. BC 1.1.) In memory of this treaty and the “Lex Sacrata” which was passed there to confirm it, an altar was erected on the spot, which thenceforth always bore the name of “the Sacred Mount.” (Dionys. A. R. 6.90; Appian, l.c.). The second occasion was during the Decemvirate; when the plebeians, who had at first seceded only to the Aventine, on finding that this produced no effect, withdrew to the Sacred Mount (Liv. 3.52). Cicero, on the contrary, represents the secession on this occasion as taking place first to the Sacred Mount, and then to the Aventine (Cic. de R. P. 2.37). Hardly any spot in the neighbourhood of Rome, not marked by any existing ruins, is so clearly identified by the descriptions of ancient writers as the Sacer Mons. Both Livy and Cicero concur in placing it 3 miles from Rome, across the Anio; and the former expressly tells us that the plebeians, on the second occasion, proceeded thither by the Via Nomentana, which was then called Ficulensis (Liv. 2.32, 3.52; Cic. Brut. 14, pro Cornel., ap. Ascon. p. 76.) Now the third mile along the Via Nomentana brings us to a point just across the Anio; and on the right of the road at this point is a hill overlooking the river, in some degree isolated from the plateau beyond, with which it is, however, closely connected, while its front towards the valley of the Anio is steep and almost precipitous.On its E. side flows a small stream, descending from the Casale dei Pazzi (apparently the one known in ancient times as the Rivus Ulmanus); so that the position is one of considerable strength, especially on the side towards Rome. The site is now uninhabited, and designated by no peculiar appellation. (Nibby, Dintorni di Roma, vol. iii. pp. 54, 55.)
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