The dozens of stone tanks that for centuries served as a 'bed' for animal skins in their transformation process, is the hallmark of the Leather Zone, in Guimarães, which has gone from anonymity to World Heritage.

Arranged side by side, forming several clusters, and with the small Rio de Couros running quietly next door, the tanks and the complex of old tanneries that surround them, called "primitive work spaces", marked the life of the Burgo de Couros, an unhealthy, proscribed and smelly area.

Today, in Guimarães, we see the Castle, the Wall, the palaces, the medieval houses, and we see the tanks, that area that, for many years, the Guimarães cartography itself did not represent. They were spaces so insignificant, so anonymous, they represented a theme of history that was so little worked on, that they were not even represented", explains architect Ricardo Rodrigues, who led the application of the Leather Zone to World Heritage Site