The Haute Route Pyrenees (HRP) follows the French and Spanish border, we started in Lescun and ended in Garvarnie. I made also a video on my 6 day hike trip: https://www.youtube.com/watch?v=PICcWp3CGcA :
A Quick & Dirty Guide to the Pyrenean Haute Route | The Hiking Life
Pyrenean Haute Route: The ultimate Guide and day-by-day hiking report
A Quick & Dirty Guide to the Pyrenean Haute Route | The Hiking Life