0 Euro - Kasteelruïne Valkenburg

EuroSouvenir's zero-denomination series has occupied a curious corner of the collector market since its 2017 launch — legal in format, genuine Oberthur paper and security printing, but carrying no monetary obligation whatsoever. The program operates under a framework negotiated with the European Central Bank, which permits commemorative production provided the face value is explicitly zero. Oberthur Fiduciaire, one of the few security printers with the credentials to produce notes indistinguishable in feel from circulating currency, handles the entire run.

Valkenburg aan de Geul's ruined castle sits atop a marlstone hill, the keep destroyed by Dutch forces in 1672 to prevent French reoccupation — a deliberate military demolition, not time's ordinary work.