Seoul in context: Street-network sprawl trends

Seoul in context

1.522.533.5<19751976–19901991–20052006–2020SNDi of street additions
1.522.533.5<19751976–19901991–20052006–2020SNDi of entire street network
SeoulGyeonggi-do (Region)South Korea (Country)

The chart above shows SNDi trends for new street additions (left panel) and the entire network (right panel), with Seoul plotted against Gyeonggi-do and South Korea. All three follow the same trend in new construction, suggesting a shared regional pattern of development. Most recently, Seoul's incremental SNDi rose from 2.49 to 3.01 between 1991-2005 and 2006-2020. In terms of the aggregate network, Seoul ranked 3rd out of 10 cities in Gyeonggi-do and 29th out of 49 in South Korea as of 2020.

New Street Additions (2006–2020)

SNDi value
3.01
Rank in South Korea
34th of 49
Rank in Gyeonggi-do
5th of 10

Entire Network (Aggregate)

SNDi value
1.98
Rank in South Korea
29th of 49
Rank in Gyeonggi-do
3rd of 10

Rankings go from most connected to most disconnected — rank 1 is the most connected.

What about similarly populated cities?

23456<19751976–19901991–20052006–2020SNDi of street additions
23456<19751976–19901991–20052006–2020SNDi of entire street network
SeoulKolkataCairo

Seoul, Kolkata, and Cairo all fluctuated in its street-construction patterns in new street construction. The same pattern holds for the full street network.