The Null Road is a road network that spreads from Origin in the cardinal directions along the "0" coordinate. The first Null Road Project was started at the beginning of the Third Era. In every era since, some sort of Null Road has existed, always built by volunteers across the world with cobblestone donations from various factions.
There is often some dispute about the design. Originally, it was designed to be an even number of blocks wide, centered on the line between the blocks straddling the 0 value of that axis of the map. Some people believe that there is a 0 block, and advocate a 3 block wide design. However, while those blocks may typically show as 0 on Rei's Minimap, if it is set to show coordinates with decimal points, any point within these blocks will be displayed between 1 and 0, g.e., 0.543.