The Fountain of Neptune, nicknamed 'al Żigànt' in dialect ('the giant' in Italian) by the Bolognese because of the size of the statue of Neptune, is the result of a collaboration between Zanobio Portigiani, Tommaso Laureti and Giambologna. The monument is associated with a curious anecdote, which tells of a particular expedient used by Giambologna, who wanted to find a way to make Neptune with larger genitals without being discovered by the Church. It seems that the sculptor designed the statue in such a way that, from a certain angle, the thumb of Neptune's hand seems to be sticking out directly from his lower abdomen, suggesting (erect) genitals; as proof of this, a black stone, also known as the 'stone of shame', has been placed in the pavement of the square at a precise point to make it easier to see.