Phantom Island refers to a landmass that has been reported on maps but does not actually exist. These islands often arise from navigational errors, misinterpretations, or myths. One famous example is Sandy Island, which was shown on maps for over a century before being proven nonexistent. Such islands can capture the imagination and lead to exploration and curiosity. The phenomenon highlights the importance of accurate mapping and the challenges faced by early explorers. Advances in technology, like satellite imagery, have helped reduce the occurrence of phantom islands in modern cartography.