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Explorers view the San Francisco Bay

Tuesday, November 4 marks the anniversary of Gaspar de Portolá’s sighting of San Francisco Bay. At 10 a.m., Association President Mitch Postel will lead a walk to the top of Sweeney Ridge in commemoration of what has been called the most important Spanish discovery in North America during 18th century. Wear good walking shoes and bring water as parts of the trail are steep.

Image: Detail of Portolá Expedition Views the San Francisco Bay, 1769 by Morton Künstler.

In 1769, Gaspar de Portolá led an expedition of 63 men from Mexico to Alta California. On November 4, 1769, they were the first Europeans to see San Francisco Bay. The sighting of the Bay was the most important Spanish discovery made in North America during the 18th century.

The expedition traveled 5 -12 miles a day following native trails. The initial contact between the Ohlone and Spanish explorers was cordial as the native people provided the expedition with food and guidance.

Spain felt it was important to settle California before England or Russia did. The expedition’s discovery of San Francisco Bay influenced how the Spanish colonial system in Alta California developed.