Sept-Forges, in the Passais region, came under the province of Maine, after a temporary annexation to the Duchy of Normandy by William the Conqueror in 1050. The fief of Mebzon was thus returned to the County of Maine.
The Mebzon mansion is a fine example of civil architecture of the Low Middle Ages in Maine. Surmounted by a magnificent frame, it offers a slender silhouette due to a lacunal part of its home, probably damaged before the Revolution, and presents a high quality implementation. Beautiful chimneys with monastic austerity punctuate vast interior rooms that have not been altered by successive occupations.
An atmosphere of great authenticity emerges from the place, with mullioned windows, coussieges, powerful frames, the formidable volumes of the two rooms of the first floor. Located on the immediate outskirts of the Mayenne river forming a 90° elbow, the manor house had a chapel, some traces of which remain on the ground.