Data sources

Last updated: 28 July 2026

Sécu'Cycle plans bike routes optimised for safety rather than distance alone. The service builds a road graph from OpenStreetMap, then gives every segment a safety score out of 10 that combines several open datasets. This page lists all of those sources, exactly how each is used, its licence and its producer.

Summary table

Road network and cycling infrastructure

The type of cycling facility, the road hierarchy, the surface, street lighting and traffic direction all come from OpenStreetMap via the Overpass API. These attributes make up a segment's infrastructure score, before penalties are applied.

The same source feeds the points of interest shown on the map: drinking water and fountains, public toilets, bike parking, repair workshops and pumping stations.

Street lighting

The street lights mapped in OpenStreetMap cover the whole service area, but unevenly. In two cities they are densified by the operator's open dataset: the Bordeaux Métropole street lights and the Nantes Métropole street lighting.

Elevation

Elevations are queried for every node of the graph from the elevation service of the IGN Géoplateforme (RGE ALTI dataset). A segment's gradient is computed from the difference between its endpoints, then weighted according to the rider's profile and whether the bike has electric assistance.

Accident records

Two national registers are used, one either side of the border. In France, the “Accidents de vélo” dataset, derived from the ONISR BAAC files. In Belgium, the geolocated road accidents 2017-2024 published by Statbel, whose Lambert 72 coordinates are reprojected to WGS84 on ingest.

Each accident is attached to the graph segments within a 25 metre radius, then weighted by exponential decay with a 5 year half-life. The resulting penalty is normalised by segment length, compressed logarithmically and capped at 1.5 points out of 10.

That cap is deliberate: these registers carry no exposure denominator, so a busy cycle route mechanically accumulates accidents without being more dangerous per kilometre ridden. The penalty is also strictly subtractive — a segment with no recorded accident keeps its infrastructure score, so that poorly covered areas are not favoured.

Live traffic

Traffic conditions are collected every five minutes from the open data portals of four cities: Bordeaux Métropole, the Eurométropole de Strasbourg, Rennes Métropole and Nantes Métropole. A source is only queried if its extent overlaps the data we sync. Where route planning is available, a congested road becomes more costly without ever being forbidden; elsewhere, the layer remains viewable on the city's thematic map.

Bike share

Station availability is collected in GBFS format from nine French and Belgian systems, by auto-discovery of their feeds. This layer is informational: it does not affect route planning.

• Le Vélo — Bordeaux Métropole / Keolis
• Vélib' Métropole — Smovengo
• V'Lille — Métropole Européenne de Lille / Ilévia
• LE vélo STAR — Rennes Métropole / STAR
• Naolib — Nantes Métropole / JCDecaux
• Vélo'v — Métropole de Lyon / JCDecaux
• Vélhop — Strasbourg Mobilités Vélo
• Villo! — Bruxelles-Capitale / JCDecaux
• Blue-bike — Blue-mobility

Air quality

The European Air Quality Index (EAQI) comes from CAMS (Copernicus Atmosphere Monitoring Service), redistributed by Open-Meteo, and sampled along the route on a grid of roughly 11 kilometres. It is complemented by ground monitoring station readings from the World Air Quality Index, published on the US AQI scale — distinct from the European index, and shown as such.

Addresses, geocoding and base maps

Autocomplete and geocoding of French addresses rely on the Base Adresse Nationale. Outside France, in Belgium in particular, they are handled by MapTiler, which also supplies the base map tiles. MapTiler is a commercial service: it is the only source on this page that is not open data, even though its base maps are themselves built on OpenStreetMap data.

Attributions

Reusing our data

Sécu'Cycle exposes a public API. The datasets we reuse remain the property of their producers and are subject to their respective licences, listed above: any downstream reuse must respect them, in particular the ODbL share-alike clause. For any question, write to us at contact@secu-cycle.fr.

See also our legal notice and our frequently asked questions.