Seoul's first entry in the atlas is a data trick born of necessity: to plan a night-bus network for a city whose subway shuts down at midnight, planners fed a month of anonymised mobile-call records and taxi trips into a grid of map cells to see where people actually moved after dark, rather than guessing. The 'Owl Bus' grew from a two-route 2013 trial to eight routes carrying roughly 7,700 riders a night by 2016, and it is still running today — one of the most cited real-world examples of transport planning built on mobile data rather than surveys.
The atlas documents 9 projects in Seoul, the earliest dating to 2005: 1 with a documented success, 8 still running without a verdict. Every entry carries an evidence grade — the strongest here is peer-reviewed (2 entries) — and links its sources.
Three entries that show what Seoul is actually doing.
Computed from the 9 entries below — a profile, not a score.
Seoul's smart-city story starts with a control room, not a portal. In 2005 the city fused live bus and taxi GPS, transit-card swipes, CCTV and roadside message signs into a single citywide operations centre, TOPIS — five years before Rio de Janeiro's Operations Center, one of the field's better-known later examples, opened for crisis response rather than day-to-day traffic. That habit of centralising real-time data to run one specific city function, rather than building a single grand platform, repeats through everything Seoul added next.
The following decade turned that habit outward, onto residents' daily choices. From 2012 the city billed for food waste by the kilogram at RFID-tagged bins (Weight-Based Food Waste Fee), and in 2013 planners mined a month of anonymised call records and taxi trips to design a night-bus network for a city whose subway shuts at midnight (Owl Bus). The same year, mVoting gave residents a mobile app to propose and vote on policy questions — extended in 2017 as Democracy Seoul, renamed Imagine Seoul in 2022, and still taking citizen proposals today. By October 2015 Seoul had completed the citywide rollout of Ttareungyi, an unmanned bike-share modelled on Paris's Vélib that has since carried more than 250 million rides.
From 2019, the target shifted from behaviour to the built environment itself. S-DoT put roughly 1,100 environmental sensor stations across streets, mountains and riverbanks, reading air quality and noise every two minutes and streaming the results to residents through the Smart Seoul Map. Two years later, S-Map rebuilt the city as a full 605 km² 3D digital twin with an Open Lab for simulating everything from sunlight to autonomous-vehicle routes, while S-Pole began folding streetlights, traffic signals, CCTV, Wi-Fi and sensors into single poles instead of separate fixtures, cutting duplicate installation costs district by district.
The most recent addition is also the slowest. Since 2022 Seoul has been swapping mechanical water meters — some a century old — for networked digital ones that catch leaks and freeze damage automatically, but the rollout is proceeding neighbourhood by neighbourhood, with full smart metering not targeted until 2040. It is a reminder that even a heavily digitised city retrofits the pipes underneath it at a much slower pace than it ships new apps.
On a time axis, by the year each one started — 2005 to 2022. Pick a dot to read what it was.
✔ Every published entry is checked against the public sources it cites before publication.
Editorial links between Seoul's own entries — the city as a system, not a list.
Plans and announced trajectories — not yet documented results.
Two threads run open from what's already built. The water-meter rollout won't reach full coverage for another decade and a half, and whether the freeze-damage reductions seen in its first pilot districts hold up as it expands into corridor-style apartment blocks citywide remains to be seen. And mVoting's companion platform has already been renamed once, from Democracy Seoul to Imagine Seoul in 2022 — a reminder that even Seoul's most established civic-participation channel keeps changing shape rather than settling into a fixed, permanent product.
Where Seoul appears in the atlas's own analysis.
Three cities the atlas reads next to Seoul — the reason first, then the entries it rests on. Chosen by hand from the Seoul threads below, not counted out of them.
Two municipal twins with opposite ambitions — Rotterdam models flooding and what lies under the street, Seoul simulates the whole city — and the same split in their sensors: a neighbourhood testbed against a citywide network.
Two traffic control towers built five years apart on the same idea, and two opposite answers on waste: Rome senses when a bin is full, Seoul bills the household by the kilo.
City-run against licensed-private, twice over: Seoul owns its bike fleet while Nanjing caps three operators who own theirs, and Seoul drew its night routes from call records while Nanjing makes the riders form the group themselves.
Every editorial link from Seoul's entries into another city, strongest first. Each one is a statement about two projects, not about two cities — the three above are the ones the atlas is willing to make at city level.
1001 Smart Cities (2026). “Smart-city projects in Seoul, South Korea.” The Smart City Atlas. https://1001smartcities.org/cities/seoul/ (last verified 2026-08-27). Data: CC BY 4.0.
The underlying data is free to reuse with attribution — see the open data page.