Located in the valley of the Tronne of Diziers at Suèvres in the Loire Valley, the Château de Bonneau was commissioned by Eugène Trégnier and built by the architect Charles-Joseph Pinsard between 1889 and 1892. The owner was a key figure in the Loire-et-Cher département, where he was mayor of Suèvres from 1900 to 1919 as much as in Paris where he was a member of the National Assembly (1906-1919) for three legislatures. Elected under a radical-socialist banner with a clearly anti-clerical position, he was also President of the General Council of the Loir-et-Cher.

An influential politician and a savvy entrepreneur in public works, Eugène Treignier naturally asked a famous architect to design a home that would correspond to his new social position. So he commissioned Charles-Joseph Pinsard, who had designed several chateaux for the industrial bourgeoisie in the Nord département, to build a residence commensurate with his success in the Neo-Renaissance style, surrounded by a vast park through which the Petite Tronne flows. This architect’s signature is engraved on a cement plaque still visible in one of the chateau’s cellars. A year before he died, Pinsard made the final alterations to the east façade in 1910, probably to extend the service areas and to remove a terrace on the first floor. Like most of his creations, the château de Bonneau is decorated using a system of red bricks with diamond shaped tracery on each of its sides. Two small turrets, including a watch tower on the left, give the main façade a “Louis XII” appearance emphasized by mullioned windows and a fantastical heraldic transom above the main door.

The Renaissance style of the decorative elements is also solidly backed by the advanced techniques used at the end of the 19th century: the entire construction in fact rests on iron arcades from the Haumont foundries, the result of technical experimentation by Gustave Eiffel. Visible from the half-buried cellars, these support the floor of a raised ground level. Iron is again used in the arches that support a brick bridge across the Petite Tronne. The internal layout of the residence is traditional; the rooms are organized out around a double flight staircase that connects the ground and first floors. The second storey, accessible by a spiral service staircase, was the floor for the servants’ rooms but it includes a surprise in the centre; the owner and patron of the place in fact kept for himself an octagonal room with carved wood panelling, with a frosted glass window lit from two openings in the roof above. This ingenious system allows the light to be filtered to create harmonious illumination conducive to work or reading.

The park is laid out over 5 hectares; it is made up of a wooded section and a landscaped area in the English style, planted with trees fashionable in the 19th century (sequoia, tulip, chestnut and plane trees). The Petit Tronne and its branches mark the boundaries of the property and supply a pond as well as a stone basin reminiscent of the Buttes-Chaumont in Paris. Anything artificial was made to appear natural; a U-shaped bend of the river, diverted from the Petite Tronne, was created to go along the alleys of the wood as if its bed had always existed. In this way, with its right-angled meanders, it is like a maze.

In the southern part of the garden, in front of the chateau, a boxwood path has been laid out, the plants are now over a hundred years old; they demarcate old flower gardens, which, with an orchard including a few surviving trees, gave the domain a certain level of self-sufficiency. This good sized boxwood, initially conceived as small boxwood borders, trace a French style garden that is accompanied by a pigeon loft built at the end of the 18th century.

On the right of this southern area, there is an annex house with a steep roof, probably intended for the groom responsible for caring for the two horses housed in the stalls that are still there.

A bucolic charm emanates from this beautifully crafted and coloured little chateau laid out in its century old garden, its woods and streams.