Eau Rouge, 1929
The stream marks an ancient border between Belgium and Prussia (1839-1919). The original circuit included a hairpin bend where the Eau-Rouge Raidillon complex is now. It was called Virage de l'Ancienne Douane, named after the customs post that had stood there. pic.twitter.com/OhLFQ0K2QL

— RDV69 (@RDV69) August 18, 2019