Overlooking the pristine blue waters of the Mediterranean, this small city-state is steeped in 700 years of Grimaldi royal history. The Palais Princier, former home of Princess Grace and current home of her son, Prince Albert II, is at the top of the cliff-bound, medieval Monaco-Ville, better known as Monte Carlo. The famous Monte Carlo Casino, an opulent example of Belle Époque architecture, is a must visit – both for its extravagance, and that of its guests. The casino is so successful in fact that in 1869, the principality stopped collecting income tax from its residents, which has made Monaco not only a playground for the rich, but also a favored place for them to live.