Extracting data from GPX files

[nordlicht]

This isn't drectly related to RC so hope there's no issues me posting this here.

I have many GPX files built up over the years and I'd like to analyse them and extract data from them.
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So RC isn't exactly for you. You could have a look at analysis software like MyTourbook or similiar stuff. MyTourbook is Open Source, you can get at least some ideas out of it if you go for your own solution.