Île-de-France: region in France
What exactly constitutes the spatial extent of the city? For these aggregations, we used the Global Human Settlement Layer Urban Center Database (GHS-UCDB) to define the boundaries of the city. These cities -- or urban centers -- cover areas that are densely populated and built-up, and so may extend beyond the spatial borders of these cities that we may be familiar with. The GHS area is shaded in blue.
View Île-de-France, France on the sprawlmap
Most recent snapshot: Taking into account the entire (i.e. aggregate) street network in Île-de-France as of 2014, the overall level of street-network sprawl is 2.12, which is relatively well-connected.
Trends in street network construction: The SNDis of street construction for the respective time periods are 1.81, 3.32, 3.21 and 3.2. Street construction in Île-de-France increased in disconnectivity initially but has since improved. The streets constructed in 1976-1990 were the most disconnected.
Quantity of street network construction: The street network in Île-de-France spans a total of 51974 kilometers. It is dominated by roads constructed prior to 1975. These roads have an SNDi of 1.81, which is relatively well-connected.
Effect on the aggregate network: New construction in each period adds to the total stock of streets, but does not change streets that have already been built. Therefore, it has a limited effect on the street network as a whole. The SNDis of the aggregate street network in the respective time periods are 1.81, 2.05, 2.1 and 2.12. Overall, the SNDi of the aggregate street network has risen: the street network in Île-de-France has become more disconnected. This increase has slowed: between 1975 and 1976-1990, SNDi rose by 0.24 points, but between 1991-2000 and 2001-2014, it rose by just 0.02.
The level of street-network sprawl in new development in Île-de-France peaked in 1976-1990. To get a sense of how street development has changed in Île-de-France, we can consider three of its most populous cities: Paris, Mantes-la-Jolie and Melun. Out of the three cities, Melun does not follow the same trend as the region. The level of street-network sprawl in new development in Melun peaked in 1991-2000.
How do development practices in Île-de-France fare in comparison to others in France? Most recently in 2001-2014, street construction in Île-de-France was the 20th-most disconnected out of the 20 regions in France. Its position in the ranks since 1975 has not changed. Île-de-France ranked 20th in 1975, 9th in 1976-1990, 15th in 1991-2000 and 20th in 2001-2014.
As of 2014, the city with the most disconnected street network in Île-de-France is Meaux with an SNDi of 3.54, which is highly disconnected. Conversely, the most connected city is Melun with an SNDi of 1.53, which is relatively well-connected. See trends for these cities: Melun, Meaux
The level of street-network sprawl in the aggregate network in Île-de-France rose steadily. To get a sense of how the aggregate street network has changed in Île-de-France, we can consider three of its most populous cities: Paris, Mantes-la-Jolie and Melun. Out of the three cities, Melun does not follow the same trend as the region. The level of street-network sprawl in the aggregate network in Melun peaked in 1991-2000.
To date, Île-de-France is the 20th-most disconnected out of the 20 regions in France. Its position in the ranks since 1975 has not changed. Île-de-France ranked 20th in 1975, 20th in 1976-1990, 20th in 1991-2000 and 20th in 2001-2014.