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The most prominent structure on the planet was Kaldor City, one of three original man-made colonies on the planet, populated by humans with sandminer robot servants that tended to their whims and also helped manage the sandminers themselves. The city itself was surrounded by the Outer Zones, which were inhabited by less wealthy members of the society. (AUDIO: Occam's Razor)
While the people of Kaldor were aware that they were descended from off-world colonists, they purposefully isolated themselves from any contact with other planets for generations, as the Company feared that it might lead to loss of profits. (AUDIO: Occam's Razor)