Looks like a couple of interesting new books on major US engineering fetes: The Golden Gate Bridge and Hoover Dam are more than just icons of American engineering. They are Depression-era monuments that transformed not only California's physical landscape, but its social one as well. The bridge linked San Francisco to rural Marin County, hastening the consolidation of the Bay Area into a huge metropolis. The dam brought reliable irrigation to Imperial Valley farms, as well as drinking water and hydroelectric power to Los Angeles and other Southwestern cities, fostering their explosive growth. Here's more from the LA Times .