After 30 years or so of researching that bread I ate in San Francisco at Fisherman's Wharf, I have scientific evidence that San Francisco Sourdough bread can be made anywhere in the world. The only problem is, for this starter, you literally start with 1/4 tsp. of bread flour and 1/4 tsp. of water. But the sponge, starter, what-ever-you-call-it isn't ready until it's been built up into 70 pounds.
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