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Flemish Roads Open the map

How Flemish Roads works

Flemish Roads is a map of roads worth riding: the famous bergs, the cobbled sectors, and the short climbs nobody bothered to name. It started with a question: where are all the climbs, not just the famous ones?

Measured from the ground up

Every road is measured against a laser height model of the ground (LiDAR), published by the mapping agencies. The profile follows the road itself, not the trees or houses beside it, and not a GPS track that smooths out the steep bits.

  1. The roads. Every road a bike may use, from open map data.
  2. The heights. Each road sampled every few metres against the ground model.
  3. The climbs. Where a road rises for long enough and steeply enough, it becomes a climb: at least 6 m up, 80 m long and 1.5 % on average.
  4. Checked by hand. The famous bergs and cobbled sectors are checked one by one and marked Verified.

Difficulty

Each climb gets a difficulty from 1 to 10, from its length, the height it gains and its steepest stretches. Some are hard to measure, like bridge ramps and earth banks: those are flagged and left off the map by default.

Cobbles

Cobbled sectors are rated in stars, like the sectors of Paris–Roubaix, because the stones make them hard, not the gradient. A climb on cobbles counts harder than the same climb on asphalt.

The route planner

The route planner runs in your browser. It knows which roads you can ride and where the climbs are, so it can draw a route through them or find you a hillier loop. Export the GPX when you're done.

Where the data comes from

Flemish Roads is independent. Race names describe the roads those races use; it has no link with the races or their organisers.

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