London tube map with distance grids

London's famous tube map sacrifices geographical accuracy to make a useful diagram. Though a boon to travelers finding their way around the complex network, it does have drawbacks: for example, the distances between stations are all wrong. This makes it hard to estimate journey times, and easy to make mistakes when traveling overground—one's mental map of the city starts to resemble the tube diagram more than the real thing. Boing Boing reader Spiregrain created a version of the map where the background is a subtle, distorted grid. Like longitude and latitude lines on a world map projection, they tell the viewer how much geographic distortion is in play in any given region. []