Designed in 1926-1927, this building is the work of François Le Coeur, an architect for the Ministry of Postal Services and an associate of Henri Royer. A circular, 17.5-metre-wide room was open to the public, while the adjoining building was reserved for employees of the postal service.
Its location between the place Royale and the apse of the cathedral makes the modernity of the building stand out.
The concrete asserts itself as a method of construction and a material. Although it does not have a coating, its bush-hammered concrete surface creates a contrast between pink sandstone and grey granite.