I visited Hillwood Estate, home of the cereal heiress who built Mar-a-Lago and was once America's richest woman. Take a look inside.

I visited Hillwood Estate, home of the cereal heiress who built Mar-a-Lago and was once America's richest woman. Take a look inside.

Hillwood Estate.Talia Lakritz/Business InsiderHillwood Estate was the home of breakfast-cereal heiress Marjorie Merriweather Post.She collected art from 18th-century France and imperial Russia for display in her 36-room mansion.Hillwood was her fall and spring home. She also built Mar-a-Lago and lived there during the winter.Marjorie Merriweather Post was once known as America's richest woman, with an estimated net worth of $250 million, or arou…