Cinderella's Château is where Cinderella, her deceased father, her dog Bruno, and her horse Major and her deceased mother once lived before her father married Lady Tremaine (who had two daughters named Anastasia and Drizella), until he passed away. Although it was, once upon a time, a grand and stately building, the narrator revealed that it had "fallen into disrepair", for Cinderella's cruel and spiteful stepmother neglected to care for it, preferring to squander the family fortune she inherited from her late husband on her daughters.
In Cinderella, the story mostly takes place inside the château. It depicts Cinderella's daily life with her helpful animal friends and her abusive stepfamily after her father's passing. It shows her doing the chores of the house and how she's mistreated by her stepmother, her stepsisters, and Lucifer, the mischievous cat. The once grand home has fallen into disrepair in the years following the death of Cinderella's father.
The only appearance of the château is at the last segment, An Uncommon Romance, where Anastasia falls in love with a baker, whom her mother forbids her to be with because he's not of a high social status. Cinderella forgives Anastasia for all of the mean things she had done to her in the past, and Cinderella and her animal friends do everything they can to help Anastasia and the baker get together.
The château makes its last appearance in Cinderella III: A Twist in Time. At the beginning of the movie, it's shown that Cinderella's stepfamily is now stuck doing all the chores that they had forced Cinderella to do in the past. But now that Cinderella's a princess and living at the castle with her husband and father-in-law, she can't do any of the chores for them anymore. The château had also lost its upkeep since Cinderella left. It's also the place where Lady Tremaine took possession of the magic wand of the Fairy Godmother and how she turned back in time to change Cinderella's happily ever after.
When Lady Tremaine turned back time, the grim condition of the château went back to being nice and clean for Cinderella was still living there at that time period. The Tremaines leave the château and move into the castle and Cinderella follows them there. When Cinderella becomes the princess again and Anastasia moves into the castle with her, Prince Charming and the King, Lady Tremaine and Drizella are given their ultimate comeuppance by being forced to work as maids at the castle. The château's fate is never indicated though it was probably sold to someone else.