0 Euro - Carnevale di Venezia

Euro Souvenir notes are issued under a licensing arrangement with the European Central Bank, which permits the 0 euro denomination specifically because it poses no monetary risk — the ECB retains strict control over the design templates, and Oberthur Fiduciaire, which prints genuine euro banknotes for several eurozone central banks, applies the same security features to these collector pieces. That last detail is the reason the series has any credibility at all: polymer thread, UV-reactive ink, and intaglio printing on a note worth nothing are not cheap to produce, and the cost structure only works because they sell in the tens of thousands through tourist venues.