500 Livres

The Banque du Liban's 500 Livres series from the late 1980s was printed against a backdrop of catastrophic monetary collapse — between 1987 and 1992, the Lebanese pound lost roughly 99% of its value against the dollar, rendering notes of this denomination effectively worthless within months of issue. Thomas De La Rue continued producing the series in London throughout the civil war period, a logistical arrangement that says much about the state of domestic infrastructure.

A watermark remains the sole security feature — thin protection for a currency under that kind of pressure.