It's probably topographical map data or provided by google earth, something like that.

Honestly -- I'm convinced that a lot of bike paths are just given an altitude that matches the street near where they are.

We have a bike path nearby that is a ton of climbing...up and down...up and down...

Think like what they build to stop noise from a highway from getting to a local town.

I know I don't get the proper numbers when I go on it with my Edge 200.

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