This map script generates a random fantasy type world. It was specifically created for Kael's 'Fall from Heaven 2' mod for Civ 4, but can also be used for native Civ 4.
Fantasy worlds often have distinct regions or valleys that have their own special climate or atmosphere. Some examples would be Mordor from LOTR, or most of the regions in World of Warcraft. Well this map script is designed to have various 'valleys' connected to one another through mountain passes, such that each region is kindof a fortress on it's own.
Here is the main discussion thread with more screen shots
Creation.py for Fall from Heaven 2 2016-10-05
Creation.py for Fall from Heaven 2