The lawless mining moon, its cavern port and tunnels now the arena of Murderbot's contract and search.
RaviHyral is the third-largest moon of a gas giant, a mining world whose single port is carved into a cavern in a mountainside, ringed by a debris-deflection grid and roofed by a clear dome that shows off the colorful mineral veins overhead. Umro has consolidated many of its claims, but security is thin and uneven, private weapons are common, and disputes are largely left to the contractors, making it a place small groups must hire private guards to visit. A transit ring above it gates all travel down by employment voucher.
Its warren of tunnels, tube lines, hotels, and abandoned dig sites conceals the erased Ganaka Pit, which Murderbot locates from old rerouting notices while guarding its clients through Tlacey's attacks.
A cavern port lit under a mineral-streaked dome, with multi-level landing slots, pedestrian tunnels, tube stations, hotels, and dim outlying mining accesses.
The dangerous, lightly policed setting of the book's action and the buried site of its central mystery.