From the Rockefellers to the Vanderbilts, meet America's outrageously wealthy 'robber barons', a term given to the 19th-century American industrialists and financiers who made fortunes by monopolising entire industries.

As well as hoarding wealth and heading up powerful families, they built some of the most showstopping residences the country has ever seen during the Gilded Age and early 20th century.

Click or scroll through to discover quintessential mansions from the time and the stories behind them....