Pope Pius IX ordered and financed the reconstruction of the ancient Marcia Aqueduct, severely damaged by the Goths in the sixth century. The work was to end in a big "show", consisting of a large circular pool, with the edge consists of a composition of rocks from which a large number of jets. In 1888, taking advantage of the development project in the area, the City commissioned a new project for a monumental Fountain to Mario Rutelli, who made four nude female figures in bronze, depicting the Naiad: Lake Nymph, recognizable from the swan, River Nymph, lying on a water monster, Nymph of Underground Waters, lying on a dragon, and the Nymph of the Oceans, riding a horse, symbol of the sea. A big jet fell on the statues, coming from the first tank inside, while the central pool kept the original design of the fountain, with a large number of jets directed towards the inside. The entire complex was surrounded by a fence. In 1912, the Fountain took on its current appearance, with the arrangement, at the center, of the Glauco group: a naked male figure grasping a dolphin, symbolizing man's dominion over the forces of Nature.