Before being renovated, the square tower of the Château de Maintenon reveals some secrets about its construction

It is considered the ancient main tower of the medieval castle, but has never been the subject of a detailed study. The crenellated square tower of the Château de Maintenon (Eure-et-Loir), however, has been revealing its secrets for several months, thanks to excavations by the department’s preventive archeology service. Built in gray sandstone on three floors, the square tower stands out from the rest of the Renaissance-style castle. The one which will be the subject of restoration in 2025 by the Mansart foundation has been the subject of new surveys to understand its transformations over the centuries.

“This tower has great architectural homogeneity. This confirms that it is from the early modern period. That is to say the beginning of the 16th century, rather than a medieval construction,” underlines Hervé Selles, head of the preventive archeology service of Eure-et-Loir. His analysis shatters the image of an old strong tower of the castle which was until then attributed to the square tower. To clarify its research, the team of archaeologists focused on the floors, the frame and the partitions and based on dendrochronology, the analysis of tree growth rings.

Coins and scrolls

The tower owes its most recent transformations to the woman who was one of the favorites and then the last wife of Louis XIV, its most recent transformations, after 1674, when Madame de Maintenon acquired the castle. The partitions which divide the ground floor and the first two floors into three rooms coincide with the opening of the windows onto the garden. Versailles-style tiles or parquet flooring on the first floor and the wall covering with woodwork make the place less austere. Woods also passed through the dendrochronology scanner, which determines their cutting in 1686. Up to four successive soil levels were found. Only the sealing impressions are kept. “These imprints in the mortars showed diagonal tiling organizations, with small tiles measuring 6 to 7 centimeters on sides,” explains the archaeologist.

In the thickness of the screeds, his team discovered a small treasure: two particularly remarkable monetary sets. The first is composed of “six coins, including three farthings from France, issued in 1655 at the start of the reign of Louis XIV”, found in the frames of the third floor. “It’s a voluntary deposit during the repair of one of the tiles,” notes Hervé Selles. The other find brings together “49 coins, all double tournaments, issued under Louis XIII, the most recent of which dates from 1643” continues the head of the department.

Archaeologists also found scraps of printed or handwritten pages provisionally dated to the 18th century in a cubicle crudely arranged at the base of a wall on the second floor. Small pieces of paper carefully nibbled by rodents.

The tower was also surveyed using photogrammetry, which allows the building to be digitized through a series of photos and which makes it possible to obtain a very realistic model. “The precision that we obtain at Maintenon is between one and two centimeters. This allows you to create a digital twin. On a 35 m high building, we zoom in down to the millimeter scale,” enthuses Antoine Louis, topographical archaeologist.

The data collected is currently being studied and will be the subject of a detailed report which will be submitted to the Mansart Foundation and the services of the regional directorate of cultural affairs. They will also be presented during a conference for the general public, on Sunday January 19 at 2:30 p.m., at the Château de Maintenon.