Aletrium (mod. Alatri), town of the *Hernici 70 km. (43 mi.) south-east of Rome. Always loyal to Rome after 358 bce, Aletrium became a prosperous *municipium (Cic. Clu.46) and remained such (reject Lib. colon.23). Its massive polygonal walls have survived almost intact, those surrounding the citadel being particularly remarkable. There is also an early *aqueduct of c.