Skiathos is a small island in the Aegean Sea, which belongs to the Sporades islands. Located near Skopelos, Skiathos is the westernmost of this island group . The mainland of Greece, along with Magnesia are to the west. Its name goes back to ancient times.

The island has the city of Skiathos and the communities Koukounaries, Kanapitsa, Vromolimnos and Troullos. The city of Skiathos is a port that houses small boats and ferry services from where they connect to Skopelos, Volos, Agios Konstantinos and the rest of Greece.

The municipality of Skiathos includes the islands of Tsougria and Repio, and has a total area of 49898 square kilometres. Its major cities are Skiathos  Kalývia , Troullos, and Koukounaries .
Much of the island is covered by forests. Around the villages and the city of Skiathos are farmland. Forests are pine, and are in the southeastern part of the island. The island of Skopelos and the most distant of Euboea and Skiros, are visible in favourable weather conditions. The top of the mountain, west, has a communications tower, and at its northern slope has several valleys.
Skiathos has about 70 beaches including a nudist beach at the southern tip of the island, at a place called Banana beach.
The island is linked to mainland Greece with sea routes to Thessaloniki, Volos and Agios Konstantinos and also with the rest of the Sporades with hydrofoils, tickets cost approximate 12 euro per person for Skopelos and 15  for Alonissos . There are also ferries for vehicles, but they are not regular at off-season . Skiathos has an airport  in the northeast of the island, which has one of the shortest runways of Europe which measures only  1570 m .
There are roads to the south, east and northwest. There is only one highway that links the four settlements on the island.