It belonged to Adam II de Chailly, Viscount of Melun and consisted of a simple manner; inside of which was a chapel, the only construction made of stone.
In the 14th century, the castle was strongly modified with new fortifications and structures of defence: a moat was dug and a new gate-tower with a drawbridge was included in the enclosing wall.
In 1888, Pierre-Charles Tuot, the mayor of Blandy-les-Tours, bought it and gave it to the municipality, no building remains in the ruined enclosure.
Acquired by the conseil général (general council) of Seine-et-Marne in 1992, the castle became the subject of a complete project of restoration, respecting the principal historical stages of the monument.
It stands 35 m high inside a polygonal enclosure of 14th century round towers.
The castle of Blandy is a typical example of a 13th-century feudal fortress, later transformed into a great lordly residence in the style of the late 14th century.