ALATRIUM or ALETRIUM(Ἀλέτριον, Strab.; ALATRINATES,Liv.; ALETRINATES,Plin. et Inscr.), a city of the Hernicans, situated to the E. of the Via Latina, about 7 miles from Ferentinum, and still called Alatri. In early times it appears to have been one of the principal cities of the Hernican league, and in B.C. 306, when the general council of the nation was assembled to deliberate concerning war with Rome, the Alatrians, in conjunction with the citizens of Ferentinum and Veruli, pronounced against it. For this they were rewarded, after the defeat of the other Hernicans, by being allowed to retain their own laws, which they preferred to the Roman citizenship, with the mutual right of connubium among the three cities. (Liv. 9.42, 43.) Its name is found in Plautus (Captivi, 4.2, 104), and Cicero speaks of it as in his time a municipal town of consideration ( Or. pro Cluent. 16, 17). It subsequently became a colony, but at what period we know not: Pliny mentions it only among the oppidaof the first region: and its municipal rank is confirmed by inscriptions of imperial times (Lib. Colon. p. 230; Plin. Nat. 3.5. 9; Inscr. ap. Gruter. pp. 422. 3, 424. 7; Orelli, Inscr. 3785; Zumpt, de Colon. p. 359). Being removed from the high road, it is not mentioned in the Itineraries, but Strabo notices it among the cities of Latium, though he erroneously places it on the right or south side of the Via Latina. (5. p. 237.)
The modern town of Alatri, which contains a population of above 8000 inhabitants, and is an episcopal see, retains the site of the ancient city, on a steep hill of considerable elevation, at the foot of which flows the little river Cosa.It has few monuments of Roman times, but the remains of its massive ancient fortifications are among the most striking in Italy. Of the walls which surrounded the city itself great portions still remain, built of large polygonal blocks of stone, without cement, in the same style as those of Signia, Norba, and Ferentinum. But much more remarkable than these are the remains of the ancient citadel, which crowned the summit of the hill: its form is an irregular oblong, of about 660 yards in circuit, constituting a nearly level terrace supported on all sides by walls of the most massive polygonal construction, varying in height according to the declivity of the ground, but which attain at the SE. angle an elevation of not less than 50 feet. It has two gates, one of which, on the N. side, appears to have been merely a postern or sally-port, communicating by a steep and narrow subterranean passage with the platform above: the principal entrance being on the south side, near the SE. angle. The gateways in both instances are square-headed, the architrave being formed of one enormous block of stone, which in the principal gate is more than 15 feet in length by 5 1/2 in height. Vestiges of rude bas-reliefs may be still observed above the smaller gate. All these walls, as well as those of the city itself, are built of the hard limestone of the Apennines, in the style called Polygonal or Pelasgic, as opposed to the ruder Cyclopean, and are among the best specimens extant of that mode of construction, both from their enormous solidity, and the accuracy with which the stones are fitted together. In the centre of the platform or terrace stands the modern cathedral, in all probability occupying the site of an ancient temple. The remains at Alatrihave been described and figured by Madame Dionigi ( Viaggio in alcune Città del Lazio, Roma, 1809), and views of them are given in Dodwell's Pelasgic Remains, pl. 92—96. [E.H.B]