Alonissos, an oblong green island, is located 35 nautical miles from Evia and 68 from the port of Volos. Thousands of years ago, a violent earthquake separated it from the now-deserted islet of Peristera. The least visited of the Sporades islands, Alonissos is an easily accessible refuge for day-trippers seeking a break from the nearby busier islands.

The main town, Patitiri, is an essentially quiet harbour featuring a few cafes and tavernas from where patrons are overlooking the comings and goings of the ferries and the fishing boats. Perched high above Patitiri is the old "Chora", a picturesque traditional village, slowly renovated after a 1965 earthquake forced its inhabitants to seek refuge in safer coastal areas. The sea-view from there is absolutely stunning. At Kokkinokastro, visitors can see the remains of the ancient city walls, tombstones and graves. Alonissos boasts one of the most renowned alternative medicine centres worldwide; seminars attracting a great number of professionals are organised there every year. Modest but adequate accommodations are provided by guesthouses and small hotels.

The sea around Alonissos has been proclaimed a National Marine Park to protect indigenous endangered species including the Mediterranean Monk seal, Europe's most endangered mammal, which can be sighted on the small deserted isles in the north. Alonissos is the perfect destination for nature lovers. Its pine forests, beautiful sandy beaches and secluded coves can be reached either by walking, or by boat. Frequent hydrofoil runs connect it to its sister islands Skiathos and Skopelos and to Aghios Constantinos on the mainland.