Beginning in 1776, Spanish, then Mexican, and finally American troops guarded the narrow, highly defensible Golden Gate Strait for two centuries because the West Coast's most important harbor was a defense priority for three nations. From the 1849 Gold Rush through World War II, San Francisco Bay ports played a key role in the United States' growth and rise to world power as gold seekers, soldiers, entrepreneurs, immigrants, raw materials, commercial goods, and gold passed through the Golden Gate. Increasingly powerful weapons positions above the strait defended this critical passage while troop ships carried soldiers to and from wars around the world.
