The local municipal council acquired the Cabot family house on Rue de Luzançay for use as its first town hall in 1752.

The central section featured a three-bay recessed opening formed by two Doric order columns supporting an entablature.

The central section also incorporated an attic level fenestrated by five small square casement windows.

[5][6] The city council moved to temporary accommodation at Château de Treulan near Sainte-Anne-d'Auray and then, from August 1944, to a boys' upper primary school on the Quai des Indes.

It was designed by Jean-Baptiste Hourlier, who was a winner of the Prix de Rome, in the modern style, built in reinforced concrete with coursed granite cladding, and was officially opened in July 1960.