For centuries, the river was the source of wealth for Vidin and Calafat.
Real estate tycoons have also done quite well, catering to the upwardly mobile and burgeoning middle classes as well as multi-nationals coming to China for business; in fact, real estate is the main source of wealth for more than a third of the 400 Chinese and at least a quarter of the country's billionaires.
He also formed companies to produce a liquid form of the explosive called a slurry, which proved an invaluable tool for companies extracting ores from open-pit mines and a source of wealth for the Cook family.
What about gold, another great source of wealth for Anglo American?
Ever-increasing home values -- the most significant source of wealth for most families -- have helped many people feel more secure.
Yet Western donors and resource companies are principally to blame for engaging in neo-colonialism, treating the country as nothing more than a source of wealth for outsiders.
Real estate and construction is the main source of wealth for 18% of UK HNWIs, ahead of financial services (15%), retail (10%) and media (9%).
They must have been aware too that they were about to destroy tourism, rightly or wrongly the chief source of wealth for the Balinese.
Perhaps most significant is the fact that manufacturing has usurped property as the leading source of wealth for the 1,000 people listed.
She has also been the source of wealth for others: Daniel Radcliffe, the 20-year-old actor who plays Harry in the films, is said to be worth £42m, while Emma Watson, Hermione, is calculated to be worth £22m and Rupert Grint, Ron Weasley, £20m.
