About a kilometer and a half from the historic center of Viggianello, you find the Sorgente del Mercure (Mercure Wellspring), the birthplace of the Lao river, also known as the Mercure river in the Basilicata region. The wellspring has a flow of 2,000 liters per second and a temperature of a cool nine degrees Celsius (48 degrees Fahrenheit). Thanks to a settling tank built in the 1920s, the crystal clear water basin flows to a hydroelectric power plant through a covered tunnel. There are few fountains where visitors can take fresh water. …
