Particularly fascinating is the effect that the Pillar Point Harbor breakwater had on the El Granada ocean bluffs, which have receded 150 feet since the breakwater was built in 1959. All the people who have lived along the shores of Half Moon Bay have used Pillar Point. For thousands of years, Native American Costanos gathered shellfish at its base. From the 1790s through the 1890s, Spaniards, Mexicans and Americans grazed long-horned cattle on its ridge. In the 1860s, Portuguese whalers sighted passing Humpback Whales from its high point and then launched their whaling boats from Whalemen's Cove just below.
Beachcombers still find fragments of whale bones in the sand.
In the 1920s and 30s, Coastside farmers grew artichokes and peas on its crown. But no one built any structures on its windswept heights. Today, it is hard to imagine how Pillar Point looked without its array of antennas and buildings. The first buildings went up during World War II, when Pillar Point was an observation post linking the Coastside to the Harbor Defenses of San Francisco. Underground bunkers built during the war still exist and are used for storage.