In this photo you can see her funeral chapel, in Anet, France.
Diane de Poitiers (September 3, 1499 - April 25, 1566) was a noblewoman and a fixture at the courts of Francis I and Henri II of France.
At the age of 15, she married a man 39 years older, Louis de Brézé, seigneur d'Anet. He was a grandson of King Charles VII who served the court of King François I. She bore him two daughters, Françoise de Brézé (1518 - 1574) and Louise de Brézé (1521 1577).
She died at 67. In accordance with her wishes, and to provide a resting place for her, her daughter completed the funeral chapel built near the castle. During the French Revolution, her tomb was opened and her remains thrown into a mass grave.
more info: [link]