0 Euro - Billet Royal - Aquarium de Lyon

The zero-euro souvenir note format was formally licensed by the European Central Bank beginning in 2015, allowing approved printers to produce legally denominated but non-circulating collectibles tied to tourist attractions. Fonderie Saint Luc, a French printing house, operates the "Billet Royal" program as one of the commercial licensees. The Aquarium de Lyon issue is straightforwardly a point-of-sale collectible — its value is entirely sentimental and philatelic rather than monetary or historical.

The watermark is the sole security feature, a nod to banknote convention rather than any practical anti-counterfeiting need for a note worth nothing.