Narrator: This is said to be the world's oldest leather-making tradition. It's called vegetable tanning, and it's a process that has been perfected over generations here in Tuscany. Artisans spend ...

The tanning process takes between three and four weeks, and 19 employees now produce 10,000 skins, or nearly a tonne, of fish leather a month. "The fish smell disappears in the early stages ...

Nearly 5sqft of leather goes into making a pair of shoes and the process leaves more than 70 grams of chemical-laced soslid leather waste.