Ischia (ēs'kyä) , volcanic island (1991 pop. 16,013), 18 sq mi (47 sq km), Campania, S Italy, in the Tyrrhenian Sea between the Gulf of Gaeta and the Bay of Naples. Known as the Emerald Isle, it is a health resort and a tourist center, celebrated for its warm mineral springs and for i... Found on http://www.infoplease.com/ce6/world/A0825558.html