Minecraft wiki entry for After_Beta_1.8, associated text: On the X and Z axies, the Far Lands and Farther Lands initiate as they did in Beta 1.7 and below (±12550824), with an identical chance of offset at positive positions. However, due to the new height limits, they are actually 256 blocks tall, instead of 128. There is a world border at the 32-bit integer limit (2,147,483,647), which crashes the game upon approaching.