Commanderie de Notre-Dame-de-la-Boissière, Medieval commandery in Châteaudun, France.

The commandery features a preserved 13th-century chapel with ribbed vaulting, nine ogival windows, and round columns topped with simple capitals that exemplify Templar religious architecture.

Gaudefroy de l'Isle gave his house to the Knights Templar in 1181, and Count Thibaut V of Blois confirmed and amortised the donation in 1183. In 1190 the count added the Boissière mill at the foot of Raffaux, parish of Saint-Valérien, where the Templars built their commandery and chapel. After the order was dissolved, the site passed to the Knights of the Hospital.

The chapel is named Notre-Dame-de-la-Boissière, a dedication to the Virgin Mary. Around 1248 the Templars of La Boissière ran a hospital for pilgrims of Saint-Jacques-de-Compostelle, recorded in the cartulary of the Madeleine abbey of Châteaudun. The chapel and commandery shared a commander with Arville and Sours, according to Abbé Bordas.

The chapel stands on Rue des Fouleries, in the narrow valley that once led from the foot of Châteaudun castle. Only the chapel survives of the commandery; it is a rectangular hall 17.40 m long, 8.10 m wide and 18 m from ground to the gable ridge. Look for the two small round-arched windows in the gable, which served as the bellcote and held two bells.

Recent 2021 renovations uncovered an ancient exterior well, interior fireplace, and engravings in the timber framework that reveal new insights into daily life across centuries.