Location from The Expanse by James S.A. Corey
First colony world beyond the Ring Gates, officially designated New Terra by the UN. Ancient Ring Builder ruins lie beneath the surface. Where Cibola Burn takes place — a corporate-settler conflict on an alien world full of things humanity doesn't understand.
Ilus is the promise and the nightmare of the Ring Gates in a single world. Breathable air, fertile soil, mineral wealth — everything a colony needs. But also Ring Builder ruins that respond to the protomolecule, alien ecosystems that don't obey terrestrial biology, and a planet-wide defense system that activates when disturbed. Belter refugees colonized Ilus first, calling it their right as the people who'd never had a world of their own. The UN sent Royal Charter Energy to exploit the lithium deposits, calling it legal claim. Murtry was RCE's security chief, a man who saw colonists as obstacles. The conflict escalated from labor dispute to shooting war while the planet itself woke up around them. Holden dealt with Ilus by talking to the protomolecule's echo of Miller, who helped him interface with the Ring Builder technology buried beneath the surface. The experience taught humanity that the colony worlds weren't empty — they were ruins, and the things that built them had left defenses that humanity's presence could trigger. Every world beyond the gates carries the same risk.
A terrestrial world with breathable atmosphere, oceans, and alien vegetation that looks almost familiar but isn't. The landscape is plains and hills under a sky with a slightly wrong shade of blue. Ring Builder ruins emerge from the terrain — massive structures of the same material as the gates, half-buried and ancient beyond comprehension. The settler town of First Landing is a collection of prefab shelters and improvised structures. The lithium deposits that drew the settlers gleam in exposed rock faces. At night, bioluminescent organisms light the landscape in patterns that seem almost intentional.
Also known as: Ilus, New Terra, Ilus IV