Olivier Penaud is a devoted bordermarker-researcher in the Basque country. See his photo-blog. In a video-recording of the French tv-series “Des Racines et Des Ailes” (from 16:40 up to the end) we see him showing us a few Basque bordermarkers and giving background information.
At the other side of the Pyrenees, the customs officer Patrick Arderiu takes us by boat to bm602 and tells about the annual reconnaissance of the bordermarkers.