- Ischia refers to both an island and a comune (municipality) located in the Tyrrhenian Sea, off the coast of Naples, Italy. The island of Ischia is known for its natural beauty, thermal spas, and picturesque towns. It is a popular tourist destination, attracting visitors from around the world. The main town on the island, also known as Ischia, is a bustling center with shops, restaurants, and historical sites.