10 Euro Herrera de la Mancha

Herrera de la Mancha, a maximum-security prison in Castilla-La Mancha, operated an internal scrip system allowing inmates to purchase goods within the facility without handling official currency — a practice with long roots in Spanish penitentiary administration. This note was produced by the Fábrica Nacional de Moneda y Timbre, the same Madrid institution responsible for Spain's official euro banknotes, giving it a level of technical production quality unusual for prison scrip anywhere in Europe.

The denomination mirrors the euro but carries no legal tender status outside the walls. FNMT's involvement was a deliberate anti-counterfeiting measure — inmates had both motive and time.