Metropolitan Lyon makes its 3D Data Reference available

Contributed by: 
Manuel Plane

For the sixth Interoperability Day organized by the French forum of the Open Geospatial Consortium (OGC) in 2012, the Lyon metropolis created a first sample of CityGML data in order to test its integration within different market tools. The program of this experiment is described at: and the presentation of the Lyon metropolis is available at : Following this first very positive experience, the Geomatics and Metropolitan Data service continued its work of entering and structuring 3D data linked to the CityGML standard.


Figure: CityGML based 3D model of the Lyon metropolis

In parallel, Open Data initiatives have been democratized and a large amount of geographical data has been made available on the Greater Lyon DATA platform: The Lyon metropolis has made its reference data available, along with data from member communities and partners (JC Decaux, Sytral, Rhône-Alpes Region, etc.). There are currently 536 data sets available, with as many as possible in open, standardized formats. This encourages interoperability, data crossing and data enrichment by third-party services.

The platform also offers access to a large amount of data through standardized flows. Information provided in real time completes the catalog and includes road events, traffic status, availability of bike-renting stations, roadway traffic tracking with cameras and the schedules for vehicles belonging to the public transportation network.

The start of the year 2015 marks a turning point with the availability under open license and open use of all the 3D models of the communities and districts of metropolitan Lyon using the CityGML standard. In this way, Greater Lyon hopes to democratize an interoperable, structured format. This technical choice is symbolic and coherent with the open data approach recommended by Open Data specialists. It denotes a wish to share data with a maximum of users by promoting a standard of the future.

The 3D models of the 58 communities and nine districts comprising the metropolitan area are available with a remarkable level of detail and homogeneous precision over 500 square kilometers of territory. With this massive release, which is eagerly awaited by a large community of users (start-ups, scientists, partners, citizens), Greater Lyon positions itself as a pioneer in the domain. An entire profession will thus be able to take advantage of this unique "big data" heritage. In return, the Geomatics and Metropolitan Data service teams hope to multiply exchanges, acquire better understanding and develop applications to help ensure that future productions meet needs as closely as possible. An experiment is currently in progress with at the LIRIS Laboratory of the University of Lyon to distribute these 3D data through a Web browser that does not require a plug-in. Here again, the goal is to propose an architecture that follows incoming OGC standards, such as 3DPS (3D Portrayal Specification).

Data opening process is accompanied by other innovations, in particular the availability of two milestones for 3D models (2009 and 2012). The analysis of territorial evolution over time is therefore a possibility and opens perspectives for new uses. As an example, the service proposes two 2D data layers on the platform that describe the evolution of building from 2009 to 2012 over the Greater Lyon area (constructions and destructions).

The technical architecture of the distribution platform is based essentially on open-source software (Geosource, Mapserver, Apache, PostGis) and follows the recommendations of the INSPIRE Directive by proposing standardized flows based on WCS, WMS, WFS and JSON. An example of WMS flow with urban planning data has been presented on the OGC France forum: 

This distribution platform aims to meet smart city goals. By providing broad access to public data, this innovative approach participates in territorial dynamism by promoting the creation of services and civic participation. An experimental site (known as TUBà) has also been inaugurated to develop activities and exchange around data. This large-scale urban laboratory aims to make the new services of tomorrow emerge through territorial companies for area residents. It currently includes a number of private companies (large groups and start-ups), research labs and cluster centers. For more information, see

To round out these announcements, the Geomatics and Metropolitan Data service has just published a didactic video on the Internet that describes its 3D data assets. Various modeling levels are presented and compared with views taken by drones that demonstrate the realism of the mock-ups! This video is found at the following address:

Author Manuel Plane is GIS Engineer at Grand Lyon.