Phantom islands (placeholder name)

Long ago, the seas were uncharted, the vast unknown on the edge of human knowledge. As explorers started going out to map the world, they returned with impressive amounts of information. The shape of the continents became known, and long journeys became, if not short, at least of a known distance. Islands were added to the charts as new lands were discovered, and the seas became crowded with nations vying to grab up every last bit of solid ground. Often, when they arrived at the point that their navigators had mapped years before, they found nothing there. But what if that wasn't the case?   ----------------------------------------------------------------------------------------------------------------------------------------------------   Until the advent of satellite imaging, a frequent problem that navigators faced was that the navigators of years passed, whose information they relied on, were wrong. Many islands were on charts, sometimes for centuries, that were later found not to exist; these are known as "phantom islands". The basic concept of this world is that these islands are actually real places, with rich histories.