Thule

Thule is the most northerly location mentioned in ancient Greek and Roman literature and cartography. First written of by the Greek explorer Pytheas of Massalia in about 320 BC, it was often described by later writers as an island north of Ireland or Britain, despite Pytheas never explicitly describing it as an island. Modern interpretations have included Orkney, Shetland, Northern Scotland, the Faroe Islands, and Iceland. Other potential locations are the island of Saaremaa in Estonia, or the Norwegian island of Smøla.