Getty ImagesThe cobblestone streets of Salvador, Brazil’s original capital city, call to mind the Raymond Chandler line that described a particularly dynamite woman: “There are blondes, and then there are blondes.” Sure, there are dozens of cities throughout the Americas with quaint colonial-era architecture. But only a few, a Cartagena or Charleston, fill travelers with such lust for the picturesque that the fetid origins of the cities’ wealth are easily put out of mind.And then there is Salvad