1911 Encyclopædia Britannica/Hadria
HADRIA [mod. Atri (q.v.)], perhaps the original terminal point of the Via Caecilia, Italy. It belonged to the Praetutii. It became a colony of Rome in 290 B.C. and remained faithful to Rome. The coins which it issued (probably during the Punic Wars), are remarkable. The crypt of the cathedral of the modern town was originally a large Roman cistern; another forms the foundation of the ducal palace; and in the eastern portion of the town there is a complicated system of underground passages for collecting and storing water.
See Notizie degli scavi (1902), 3.