In 1558, Venetian nobleman Nicolò Zeno published a map he found in his family’s archives. It was created by his ancestors during their expeditions to the North Atlantic and Arctic. The “Zeno map”, as it became known, became very influential among early cartographers. However, Zeno’s ancestors had mistakenly thought that southern Greenland was a separate island, which they called ‘Frisland’. This phantom island was replicated on all other maps for 100 years, until later explorers proved it didn’t exist.