Alonnisos, also transliterated as Alonissos, is a Greek island in the Aegean Sea. After Skiathos and Skopelos it is the third member of the Northern Sporades. It is 3 km (2 mi) (2 nm) east of the island of Skopelos. Alonnisos is also the name of a village on the island, as well as the municipality that encompasses the island and the village.

Skopelos is a Greek island in the western Aegean Sea. Skopelos is one of several islands which comprise the Northern Sporades island group, which lies east of the Pelion peninsula on the mainland and north of the island of Euboea. It is part of the Thessaly region. Skopelos is also the name of the main port and the municipal center of the island. The other communities of the island are Glossa and Neo Klima (Elios). The geography of Skopelos includes two mountains over 500 m (1,640 ft); Delphi (681 m/2,234 ft) in the center of the island, and Palouki in the southeast. With an area of 96 km2 (37 sq mi) Skopelos is slightly larger than Mykonos (85 km2/33 sq mi) and Santorini (73 km2/28 sq mi). The nearest inhabited islands are Skiathos to the west and Alonnisos to the east.