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Mediterranean seacoast around Genoa, 1630s, from Italian riviera, literally "bank, shore" (see river). In extended use, the coast from Marseilles to La Spezia, which became popular 19c. as a winter resort. Thence adopted (sometimes ironically) in reference to areas of other countries, e.g. American Riviera (Florida, 1887); English Riviera (Devonshire coast, 1882).
Note: Its scenic beauty and mild climate make it a popular vacation area.
Note: The French Riviera is also called the Côte d'Azur (the azure coast).