The interactive digital special project "Mercator. It’s a Flat, Flat World" tells the story of a famous map, published in 1569 by the flemish cartographer Gerhard Mercator. We describe the historical and scientific context of the epoch and share the personal story of its' creator. The key visual of the project is the map itself. We point at the mistakes, some curious facts and the unconditional advantages of this innovative projection, that glorified Mercator's name.