ulkorenkaiden

Ulkorenkaiden is a concept in speculative urban design and worldbuilding that refers to the outer ring districts surrounding a central urban core. In fictional geographies it denotes a defined belt of settlements, neighborhoods, and infrastructures forming a secondary ring outside the city center.

Etymology: The term combines Finnish ulko ("outside, exterior") and renkaiden ("of the rings"), indicating its intended geometric position as outer rings.

Design features: Ulkorenkaiden zones are typically linked by radial and circumferential transit networks, include mixed-use zones, housing clusters, industrial belts, and green buffers. They are conceived to absorb growth, reduce pressure on core districts, and provide modular resilience against climate or disaster shocks.

In narrative usage: In science fiction and game lore, Ulkorenkaiden is used to explore tension between central authorities and peripheral communities, resource distribution, and the evolution of peri-urban life.

Related concepts include ring city and peri-urban belts.