Pytheas was Massilia’s premier explorer, famous in his lifetime for travelling to northern Europe by sailing through the Straits of Gibraltar and along the Iberian and Gallic coasts into the English Channel and beyond. Although there is a possibility southwestern Britain was previously visited by Carthaginian traders in the 5th or 6th century BC, Pytheas was among the first Greeks to visit the island. However, it seems likely that he travelled much further north than his predecessors had dared. Even though his own account of the journey has now been lost to history, it was widely-distributed at the time. In it, Pytheas apparently described the colder climate and phenomena of the midnight sun, indicating that he sailed to the Arctic Circle. A supremely bright and insightful individual, he is also significant for understanding much of what he witnessed, being the first to postulate that the behaviour of the tides is connected to the cycles of the moon, for instance.
