During the Age of Exploration, cartographers often succumbed to the temptation to insert imaginary topography in places about which little or nothing was actually known.
This map of the eastern part of North America features a prominent, entirely fictitious, mountain range extending from Michigan into Florida, connecting with the Appalachians along the way. The map is based on numerous Jesuit and French sources of information on the Great Lakes and Canada. The error was perpetuated on maps into the nineteenth century.
Off the eastern seaboard is a large inset map of the North Atlantic, showing the eastern part of North America and the West Indies, as well as the coastlines of Europe and Africa. Above that is a smaller inset of Boston and vicinity.