0 Euro - Cathédrale de Monaco

The 0 Euro souvenir note program was launched around 2015 by the UEFD as a legal-tender-adjacent collectible — technically denominated, never redeemable, and designed to exploit a gap in EU regulations that allows member and associated states to issue novelty notes carrying the Euro name without the backing of the European Central Bank. Monaco, as a microstate with a monetary agreement with the EU, makes a natural subject for the series.

Oberthur Fiduciaire, the French security printer, produces the physical notes to genuine banknote specification — correct paper, UV features, and serial numbering — which is precisely what gives the format its appeal over a simple postcard.