Take a look inside a historic 54-room Gilded Age mansion that belonged to one of America's richest families

• The Vanderbilt Mansion in Hyde Park, New York, was built by Frederick Vanderbilt in the 1890s.
• The 45,000-square-foot Gilded Age mansion is located on 153 acres of land in the Hudson Valley.
• The National Park Service offers tours of the mansion to the public.

During the Gilded Age in the late 1800s, railroad tycoon Cornelius Vanderbilt was the richest man in America with a net worth of $100 million, or around $200 billion today — more money than the US Treasury had at the time.

After Cornelius' death in 1937, his son William Vanderbilt took over the businesses and doubled his father's fortune. He died the wealthiest private individual in the world in 1885.