MCEdit

MCEdit is an open source world editor for the popular game Minecraft. MCEdit was first created to allow players to preserve anything built with several old versions of Minecraft and take them forward into newer versions of the game.

Free Open Source Windows Linux Mac Java Minecraft OpenJDK

WorldGuard - Minecraft Plugin

WorldGuard is a powerful plugin with a large bag of tricks for server owners, server map makers, regular survival servers, and everyone in between!.

Free Open Source Windows Linux BSD Mac Minecraft Server

WorldEdit - Minecraft MOD

WorldEdit is an easy-to-use in-game Minecraft map editor. Through a combination of commands and "brushes," you can sculpt your world or simply perform numerous...

Free Open Source Windows Linux BSD Mac Minecraft Forge