12 meters high, the fountain is built of cold stone and composed of two basins. Lions, dolphins, swans and children, works by Truphème, decorate it. The three statues which surmount it represent Justice (towards Le Cours), Agriculture (towards Marseille) and Fine Arts (towards Avignon), forming a road star. Ramus, Chabaud and Ferrat are the authors.

The Hôtel de Caumont is located in an aristocratic district of the old town of Aix-en-Provence, the Mazarin district. Of Parisian influence, it is a hotel "between courtyard and garden", an architectural scheme that appeared in Paris in the 16th century, which, reported on an urban scale, corresponds to the castle and its park. This type of construction "between courtyard and garden" disappeared in 1680 in Aix-en-Provence, favoring the construction of hotels on the street to stand out from the Parisian style. The portals are then more decorated in a baroque tendency characteristic of southern taste. By the scale of its design without equivalent in Aix-en-Provence, it represents a sample of French architecture of the 18th century. For their quality, the carriage gate, the facade and the wrought iron stair railing were listed in the additional inventory of Historic Monuments in 1925. The entire hotel was listed in 1987.

Among the paintings exhibited in the church, Delacroix's Crucifixion is the one that attracts the most visitors. Several stained glass windows are inside. The stained glass window dating from 1854 has the Baptism of Christ as its main theme.

The fountain in the center of the square, the work of the sculptor Jean-Claude Rambot in 1667, represents four "architectural dolphins" surrounding a pyramid which was originally crowned by a statue of Saint Michael. The statue was successively replaced by a fleur-de-lis, a Maltese cross, then a pinecone.