This is about one of my best friends! He is an amazing local historian and a staunchly wedded empiricist, a resident of SF in the deep, old way. I highly recommend taking one of his ThinkWalks if you want to learn about local history, ecology, and the meeting of the two. http://www.thinkwalks.org/
Also check out his amazing water map of SF, which is both beautiful AND accurate: http://seepcity.org/
Also check out his amazing water map of SF, which is both beautiful AND accurate: http://seepcity.org/