Blue Marble is a terrain graphics mod for Civ4 created by ColdFever/Kai of civilized.de. This thread gives details. The high and low resolution versions at now at the following links: UPDATED November 30, 2008: These links point to version 4.50 Gold of BlueMarble. Thanks ColdFever. UPDATED August 25, 2009: These linked zip files now include the files required for use with Beyond the Sword UPDATED September 2 2014: Links to the download files have changed. High resolution for those with high performance systems Low resolution for the more challenged Macs. The expanded files and folders are in a top level folder called CustomAssets. They go into your own ~/Documents/Civilization IV[ Warlords][ Beyond the Sword]/CustomAssets/ folder, replacing the empty folders that are there already. WARNING: If you already have a mod installed there then this will replace it. If anyone is interested, I have updated my Drag and Drop Mod Installer to work with Blue Marble, and any other mod that comes in a zip file with CustomAssets as its top level folder. This version is here. - Download it and open the disk image. - Drag the Mod Installer application to /Applications/ and launch it. - Select Civilization IV in the popup menu at the top. It should look for Civ4 on your hard drive and show it as an entry in the window. - If this doesn't happen, drag your /Applications/Civilization IV/ folder into the window. - When your Civ4 folder is listed in the Mod Installer window, drag the BlueMarbleHighRes.zip or BlueMarbleLowRes.zip file onto its icon. Confirm that you want to proceed, and it should install Blue Marble in your CustomAssets folder. - Launch Civ4 and marvel at the new terrain graphics. Mod Installer hasn't had a lot of user testing, and none since I added Civ4 to its repertoire, so any feedback you can provide will be welcome.