Herculaneum, ancient city of 4,000–5,000 inhabitants in Campania, Italy. It lay 5 miles (8 km) southeast of Naples, at the western base of Mount Vesuvius, and was destroyed—together with Pompeii, Torre Annunziata, and Stabiae—by the eruption of Vesuvius in 79 CE. The town of Ercolano (pop. [2021 est.] 51,600) now lies over part of the site. The excavations of Herculaneum and Pompeii in the mid-18th century precipitated the modern science of archaeology. Collectively, the ruins of Pompeii, Herculaneum, and Torre Annunziata were declared a UNESCO World Heritage site in 1997.