Air Central (aka Airways)
The hub for world transportation. Taking up a square mile of Centropolis, it is a vast industrial complex with landing areas (47). Secretly controlled by the tendrilless slans, they surreptitiously launch ships into space while the rest of the world believes space flight is legendary or has never been accomplished (47).
Bureau of Statistics
A repository of information in Cimmerium, containing vast storehouses of knowledge on countless subjects. Census statistics on the tendrilless slans living on Mars were held here (156), as well as important historical records (174-5).
Catacombs, The
An extensive network of caves beneath Centropolis. Slans had created secret passages into the catacombs. Peter and Patricia Cross knew some of these routes, but both died before they could show them to Jommy (57). Fortunately, as part of the hypnotic education given to his son, Peter included detailed instructions on how to reach the weapon hidden in the catacombs, regardless of the entrance point (61). The catacombs were accessible through numerous locked entrances in public places. Now abandoned, they are protected by automated alarm systems that alert the authorities when they are entered (60).
Centropolis
Capital of the world, located somewhere on the Eastern coast of North America, about one hour's flight east of the Rockies as the slanship flies (73). It is a vast city with an enormous population, notable for its many parks and skyscrapers (5). Controlled briefly by the slans, who built the palace there (5).
Flowing through the city is a single wide, deep river that goes right by the palace (15, 176). Mountains are visible on the horizon (15). It is surrounded by suburbs, one of which was the residence of Jommy and his mother for a while (5).
Cimmerium
A large tendrilless slan city built into a canyon near the Mare Cimmerium on Mars. Like most cities on Mars, it was covered by a protective dome. Although not very large as cities go, with a population of 200,000 (162), it was probably the tendrilless slan capital. Cimmerium was the location of a major spaceship factory (157) and was the staging point for the tendrilless' planned invasion of Earth. This staging field extended for at least a hundred miles and was heavily fortified with fleets and massive gun emplacements (161).
The architecture in tendrilless cities was beautiful, and of a style that Jommy compared to poetry (165). The tendrilless retained the secret of the building material that the true slans used to create the Palace, and employed this material to construct their cities (170).
The city was many levels deep, with the bulk of the city being underground (165, 170). Cimmerium's landing field and vast underground hangar is interesting: each ship is stored in a slot and could be brought out by machines by dialing the number of its parking space (162).
Cugden Machine works
A location where devices and machines can be dismantled and reverse-engineered. They undoubtedly also do many other heavy-duty industrial tasks. The slan ship that dropped the message at the palace was forced down and taken to Cugden for study (82).
Granny's Shack
A small, dirty, ramshackle house and barn surrounded by piles of junk, sitting near a meadow situated somewhere within Centropolis. The palace was visible in the distance (41-3).
Granny's Valley Ranch
Located in western North America (148) this ranch was purchased using some of the funds collected during their years of thieving (122). Jommy and Granny lived in this secluded valley for seven years (124, 147). Apart from being a fully functional ranch on the surface, beneath the ground there was a vast network of weapon emplacements (151), storage space for his ship and car (126), and his laboratory where everything was controlled (123, 150). The inside of a nearby mountain was converted into a fortress (123). His ship was hidden 20 miles away from the ranch, near a mountain (147). The house and laboratory were constructed of ten-point steel, thus protecting them from much of the destruction of the tendrilless attack that leveled the mountain fortress and obliterated everything inside it (149). After the attack, Jommy left his laboratory and all of his devices to self-destruct behind him to prevent the tendrilless from acquiring his research and inventions (151-2).
Mars
A cold and barren world, it was terraformed in the distant past by bombarding its surface with asteroids composed of ice and frozen oxygen (153). The seas created by this process are described as being "unclean" and "unbeautiful" (161).
Long ago Mars was made into the stronghold of the tendrilless slans, the only race to have space travel capabilities when the story takes place. Its surface is a mixture of desert and small seas, dotted with domed cities and smaller, more isolated settlements. Mining operations on Mars were mostly automated, requiring very little supervision (154). The largest city is Cimmerium, built in the Mare Cimmerium.
Palace, The
Built by slans during their golden age hundreds of years in the past, it is a vast, magnificent, delicate-looking structure 1500 feet high. Made out of an unknown material, its exterior softly glowed and constantly shifted colors at random (43, 90). The tendrilless slans retained knowledge of this substance and used it in their cities on Mars (170). The main structure is 1,000 feet high, topped with a 500-foot tower (43, 90). There were airplane hangars at the 1,000-foot level (132) and battlements at the 500-foot level. Kathleen was not allowed to go any higher than 500 feet in the palace, but often enjoyed looking out onto the magnificent view of the city from there (15). Her bedroom and Gray's office were on the same floor, somewhere below the battlements (17).
It can accommodate about 10,000 people (177). Since the slans secretly controlled the government, there were usually at least 100 slans living in the forgotten areas of the palace at any given time (188).
Heavily defended by guards and large weapon emplacements, the palace is well-nigh impossible for intruders to gain entrance. Each group of guards is under a separate jurisdiction, and passes are required for free passage from one area of the grounds to another — these precautions were created in response to rumors of the tendrilless attack on the valley where Granny and Jommy lived (177).
Although currently held by humans, it still contains many secret chambers, including treasure troves of technological devices and weapons that humanity thankfully remains totally unaware of (43). There are many tunnels and passageways into the palace, most of them long forgotten and unknown. A vague record of many of these passages is retained in the Statistics Machines (173, 175). Some passages were marked with Porgrave machines to guide nearby slans to them (178). These vast underground areas were once functioning parts of the palace, but have since fallen into disuse and obscurity (180).
Also called the grand palace (6).
Slan Refuge
A vast subterranean city, one of many in the world. It is self-sufficient, containing "factories, gardens, and residences" (134). It has its own water supply in the form of an underground river (137). A Porgrave thought broadcaster sends out looped automated messages directing slans to its secret location (134). The city is beneath an uninhabited farmhouse which was specially constructed to give the appearance of being dilapidated (135). Apart from the two main entrances, there were multiple secret exits to allow quick escape from any point in the city (139).
The refuge was probably centuries old (141). It was discovered and raided about 25 years before Kathleen and Jommy visited it, its inhabitants fleeing (137). One of dozens of such refuges known to the government, it was used as a trap for stray slans (131). It was two hours' southwest of Centropolis by flight (133).
