HYDRUNTUM, in Ancient Geography, a noble and commodious port of Calabria, from which there was a shorter passage to Apollonia. It was famous for its antiquity, and for the fidelity and bravery of its inhabitants. It is now Otranto, a city of Naples, situated at the entrance of the Gulf of Venice. Long. 19. 15. E. Lat. 40. 12. N.