The Pont-Neuf and the area around it, and the westerly tip of the Île de la Cité in Paris were created by Henri III in 1578. The beauty of this setting and the symbolism of its proximity to the Palais de la Cité (residence of the kings of France from the 10th to the 14th century) all made it a favourable place for architectural projects. Germain Boffrand (1667-1754) had already, in 1748, designed a semi-circular building, but it looked towards the palace. In 1780, Louis François Petit-Radel (1740-1818) proposed a scheme to extend the palace, now the Palais de Justice, with a colonnade, also semi-circular. In the mid 19th century, as part of the proposal to modernise the palace, there was an idea to incorporate the Place Dauphine, situated between the Pont-Neuf and the Palais de Justice. At the end of the 19th century, faced with the dilapidated state of the square, there was talk of radical renovations. This was the context in which Varcollier put forward his proposal, one more in a succession of ideas either to enhance the bridge and its central section or to redevelop the Palais de Justice.
The architect proposed a huge rotunda recalling the Coliseum in Rome, and whose layout was astonishingly close to Boffrand's. The semi-circular design brings out the full impact of the shape, and is a Roman reference. The use of arched windows is a motif that runs through both his public and his private building projects. This classical vocabulary, giving prominence to the orders and decorative elements, makes it closer in style to the buildings of the first half of the 19th century than to those of his own time.
On the other hand, this drawing reveals nothing about the origin of the project. Was it made for the owners of the land who hoped to divide up the square for resale, or for the city authorities who were worried about the dreadful state of the square? It could equally have been a personal idea of Varcollier's. As an architect of the City of Paris, he must have known this place very well and wondered what might become of it.