In Medellín, Colombia, a cool mist rises from the streams that bubble down the mountainside and wend through oases of bamboo and broad-leafed trees. At 5,000 feet, the weather is perfect. A typical day—year round—is sunny and in the mid-70s F. You won’t need air conditioning—nor even screens for your windows—as bugs are almost nonexistent. The physical beauty, perfect weather, and First-Worldliness of this city are big draws. But I’m not here on vacation….

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