Nerthus is Carsten's Star III on the Sagittarian frontier of the Stellar Union. Colonists, like Solarians, live far apart because they are easily connected by telescreens and gravity fliers. However, trade with nearby planetary systems necessitates spaceports, warehouses, depots, service and repair facilities, shops, robot factories, entertainment and administration, therefore cities, although usually only one per planet or planetary system.
The Nerthusian city, Stellamont, has a Coordination Service base and an old section including the native quarter which is inhabited by tall, green-furred, four-armed bipeds and their six-legged draft animals.
Further, the galaxy is mapped with reference to constellations as seen from various base planets which include Nerthus. This is a good example of a location in one installment of a future history series becoming part of the established background of later installments of that series. Anderson could have added a lot more stories in this setting but instead went on to write many other works including several other future history series.