San Pellegrino water is produced in San Pellegrino Terme. The water may originate from a layer of rock 400 metres (1,300 ft) below the surface, where it is mineralized from contact with limestone and volcanic rocks. It emerges from three deep springs at a temperature of about 22 °C (72 °F). The springs are located at the foot of a dolomite mountain wall which favours the formation and replenishment of a mineral water basin. The water then seeps to depths of over 700 m (2,300 ft) and flows underground to a distant aquifer.