The keep (donjon) of Chambois Castle is located in Normandy and is a classic Norman style stone keep. It was built in the second half of the 12th Century when the kings of England were still lords of Normandy.
The donjon is a rectangular building with square buttress-like towers at the corners. The entrance to the keep is on the second level and was reached by a wooden staircase. The machicolated parapets were probably added in the 15th Century.
My reconstruction of the Donjon of Chambois is 25 x 30 inches (80 x 96 studs) and is 24 inches high.
For more photos of my reconstruction of the Donjon of Chambois
For photos of the real Donjon of Chambois and other source