Few towns have the identification of Leintz Gatzaga on a specific economic activity. In this case, it has been the salt industry, an activity that promoted the creation of the town.
Salt production has given the town its name and a tower and two dorlas (cauldrons for obtaining salt) appear on the Salinas coat of arms. The salt source is located 250 meters from the town, next to the old Dorlas castle. Today it has been restored and those who come to visit it can see the reproduction of the wooden bucket wheel.
In 1834 the great floods in the valley destroyed the salt mine and put an end to manual exploitation. The exploitation went to the company Productos Léniz, which rebuilt and expanded the facilities and established a hydraulic system to extract water from the salty well at a depth of 7 meters and take it to the dorletas: the wheel of jugs (currently reconstructed in the museum) . At that moment the industrial phase of exploitation will really begin.