Throughout history, civilizations have populated the perceived "edges" of the world with legends and monsters.
: As early as the 7th century BC, the Babylonians mapped the world as a disc surrounded by "bitter waters," beyond which lay seven mystical lands. These regions were described as the place "where the winged bird ends not his flight". Space Legends At the Edge of the Universe
: The "edge" of our universe is not a physical wall but a limit of information. Because light takes time to travel, we can only see objects within a bubble roughly 93 billion light-years in diameter. Space Legends At the Edge of the Universe