one dataset · paper, tables, graph, wiki
simgrammar the grammar of simulation

parts

17 mechanics, as Cities: Skylines does them

core · 4

logistics & networks

Public transit lines

Player-drawn bus, tram, train, metro, ferry, and taxi lines carry passengers, cut congestion, and earn fares.

logistics & networks

Road networks

Road type sets lanes, speed, and zone frontage; network geometry such as interchanges and one-way systems decides throughput.

logistics & networks

Traffic congestion

Each citizen takes the fastest route to work or other destinations; poor road design shows up as visible jams that delay services and deliveries.

space & construction

Zoning

Zoning cells follow the shape of drawn roads; residential, commercial, industrial, and office zones develop and level up.

supporting · 13

agents & behavior

Agent pathfinding

Citizens and vehicles path individually through roads, paths, and transit.

space & construction

Building placement

population & lineage

Education and workforce

Elementary (300), high school (1,000), and university (4,500) capacities move citizens through four education levels that higher-level jobs require.

logistics & networks

Fluid pipe networks

Water and sewage pipes; sewage released upstream contaminates downstream intakes.

economy & finance

Land value

Services and parks raise land value, pollution and noise lower it, and land value helps buildings level up.

population & lineage

Lifecycle and aging

Citizens age and die; an initial cohort moving in together can age into a wave of deaths that overloads hearses.

progression & goals

Milestone unlocks

Population milestones unlock services, zoning types, policies, and purchase of up to 25 map tiles.

multiplayer & persistence

Modding API

Steam Workshop and a mod-friendly architecture; mods add assets, maps, and new behavior.

governance & policy

Policy toggles

District policies restrict development types, set district tax rates, or make transit free.

resources & production

Power grid

logistics & networks

Service coverage

Service buildings reach buildings by network distance and dispatch vehicles.

logistics & networks

Travel mode choice

Citizens choose between walking, driving, and the player's bus, tram, train, metro, ferry, and taxi lines when routing to destinations, so new lines shift demand off roads.

watch

1 short with this record on screen
Short 8: City builders don't tell stories, opening frameplay · 0:38
rendered · short-08.mp4 · drawn from the dataset

short 8 0:38

City builders don't tell stories

transcript

Only one game in our catalog lets you place buildings and also runs chains of story events: 77 games do the first, 17 the second.

In Cities: Skylines, a district built all at once grows old all at once. Decades later its residents die in a wave, and the hearses back up. The game treats it as a services problem. Nothing tells you a story about any of them.

The exception is Surviving Mars, which lays authored mysteries like plagues and AI revolts over a colony you lay out yourself. Even there, the mysteries are layered on top of the colony.

also on the pages for

core loop

draw roads and zone along them -> citizens move in, commute, and shop along computed routes -> population milestones unlock services and map tiles -> set district policies, taxes, and budgets -> fix traffic with road hierarchy and transit -> expand

design notes

Colossal Order carried the road and transit systems of its Cities in Motion series into a full city builder, so every citizen and vehicle is an agent taking the fastest route and congestion is read directly from visible jams. Zoning cells are generated along whatever road geometry the player draws, freeing layouts from a fixed grid, and districts let the player apply policies and tax rates to painted areas. Paradox approved the project after the reception of SimCity (2013), the game was built for Steam Workshop mods, and widely used mods replace core systems such as traffic rules.

appears in

the paper, 3 sections · 9 chapters · 3 episodes · 1 short
paper

3. The catalog

linked in this section of the paper

paper
paper

5. The structure of the design space

linked in this section of the paper

paper
paper

Appendix A. Game catalog

linked in this section of the paper

paper
catalog

The catalog

listed with its year, developer, subgenre, and number of mechanics

book
ch 2

Chapter 2. Six layers

linked from the text

book
ch 3

Chapter 3. Old parts

named in the text

book
ch 4

Chapter 4. Families

linked from the text

book
ch 5
book
ch 6

Chapter 6. Five ceilings

named in the text

book
ch 7

Chapter 7. What shipped

named in the text

book
ch 9

Chapter 9. Vacant lots

linked from the text

book
ch 10

Chapter 10. Bets

named in the text

book
ch 12

Chapter 12. Keeping score

named in the text

book
ep 4

Why deep systems are hard to read

on screen at 4:15 expensive and hidden

episode
ep 5

The five ceilings

on screen at 6:34 lifting one ceiling spends another

episode
ep 8

Vacant lots

on screen at 0:00 cold open, 3:56 workers who grow old

episode
short 8

City builders don't tell stories

0:38 · on screen in the short

short

relations

1 stored edges
influenced by

claims

1 with sources
c01medium

Cities: Skylines is credited with reviving the SimCity style of city builder after SimCity (2013).

src-wikipedia-city-building-game, src-wikipedia-cities-skylines

sources

3
Wikipedia contributors (2026). Cities: Skylines. Wikipedia
Cities: Skylines Wiki contributors (2026). Education. Cities: Skylines Wiki (paradoxwikis.com)
Wikipedia contributors (2026). City-building game. Wikipedia

provenance

runs in log/runs
2026-10-24
created2026-10-24-catalog-gacatalog
2026-10-24
reviewed2026-10-24-review-fixesmaintenance
2026-10-25
reviewed2026-10-25-store-ids-pilotcatalog