Eastern Pacific High Sea

The coastal waters facing San Francisco sit beside land inhabited for millennia. Archaeological traces place human habitation in the area as early as 3000 BCE. When the Portolá expedition arrived overland on November 2, 1769, the Yelamu group of the Ramaytush lived in several small villages; the bay’s Ohlone name, Ahwaste, means “place at the bay.” Spanish colonization and the mission system then brought assimilation and decline for Ramaytush language and culture.

The incoming sea shaped the coast as strongly as its history did. Cool Pacific currents moderate temperature swings, while summer heat inland draws winds from the North Pacific High through the Golden Gate, producing the characteristic fog and cool breezes of the bay. Summer fog can cover the coastal approaches while eastern shores remain clearer. New Spain established both a presidio and Mission San Francisco de Asís in 1776. Its successive communities shared one setting: a sheltered bay reached from open water through a narrow coastal gateway.