A variation of this soup runs through most of the alpine regions of France, including the Provencal Alps and the Pyrenees. In these areas, the high concentration of vitamin C present in garlic is looked upon by shepherds-and doting mothers-as a means of warding off winter's ills. Most rustic recipes simply call for stirring egg yolks into the finished soup. This version, with its whole poached eggs, comes from the departmental capital of Digne, long a stopping-off point for alpine tourists and well known for its thermal baths. The city lies on the famous road built by the Romans through Italy to northern France, a byway that later became la Route Napoleon.