The origins and history of the château de Roanne are little known to us. Studies on the current building, carried out in 1999, revealed no element prior to 1225 for the dungeon and to the 15th century for the castral buildings.

Erected outside the borough, it is likely that the château housed, at the end of the 12th century, a few dwellings, protected by a first enceinte. Thanks to Guillaume Revel, charged with portraying all the châteaux coming under the Duc de Bourbon (who also became Comte de Forez), there is a view of Roanne dating approximately from 1460. It shows a modest château, of mediocre military value. One can recognise the dungeon on it.

In the second half of the 15th century, the château no longer served as a residence for the lords of Roanne. It was used as a prison and as a court, until the latter was transferred to the Couvent des Ursulines, at the beginning of the 19th century.

Of this château, there remains today only the dungeon and the building which is attached to it. The dungeon is 20 metres high. It is constructed from cobblestones and small blocks of Villerest granite. It is the town's oldest building. It bears the traces of numerous alterations: openings made and openings filled in, masonry repairs. It was listed in 1931.

The adjacent building was converted into a dwelling house in the 19th century. A Renaissance style façade was added to it. The Town acquired the whole of the building in 1997.