World History

in which the voyage of Pytheas is a major theme. The books, whose names translate as Silverwhite and More Silverwhite, were published in 1976 and 1984 by the late Lennart Meri (1929-2006), a former president of Estonia, writer, producer and film director. Unfortunately these books have not been translated into English, only Finnish, Italian and Russian.

My vocabulary is not adequate to understand everything in Meri's books, but he presents an interesting theory that Pytheas sailed far into the Baltic Sea to the Estonian island of Saaremaa. Meri bases some of his theory on the sunrise and sunset times at different points of latitude as recorded by Pytheas.

Wikipedia: "Hõbevalge is based on a wide-ranging ancient seafaring sources, and carefully unveils the secret of the legendary Ultima Thule. The name was given in classical times to the most northerly land, reputedly six days' voyage from Britain. Several alternative places for its location have been suggested, among them the Shetland Islands, Iceland, and Norway. According to Meri, it is possible that Thule derives from the ancient Estonian folk poetry, which depicts the birth of the Kaali crater lake in Saaremaa."

Another source: "His account is strained by surprising hypotheses, the main one of which is that the ancient mariner Pytheas travelled as far as Saaremaa in his journeys and called it Thule."

His theory has been derided by some, but I find it fascinating nonetheless.