It is a fairly unstable world orbiting binary stars. Mainly desert and volcanic, Durux holds little in terms of resource value. For military purposes, it is ideal for setting a foothold for scouting out the other races. As such many try to invade, settle, and hold base on the world. After the Brood War, the Zerg held a firm claim to the planet despite the constant sieges from the Terrans.
For the interim of the two Great Wars, no one has ever retaken Durux. It was not until after a short time into the Second Zerg War that the planet was weakened enough to be up for grabs once more.