DID YOU KNOW?

The Bay stretches up to 13 miles side-to-side and 40 miles top-to-bottom. Before Americans arrived in 1880, the Bay covered 800 square miles.

 More than 90% of the Bay’s original wetlands have been lost to development.

 Salt has been a major Bay Area industry since 1853. The extensive salt ponds of the South Bay provide table and industrial salt to the world.

 Before 1910, California’s top commercial fisheries—oysters, salmon, sturgeon, shrimp, sardines—operated in the San Francisco Bay.

When it opened on November 12, 1936, the San Francisco-Oakland Bay Bridge was the longest bridge in the world, spanning four and a half miles over water. It was also the world’s heaviest structure, containing more concrete than the Empire State Building.

WWII’s post-war settlement of returning GIs to the Bay Area caused a population boom and reshaped the shoreline in major ways.

Many of the buildings that form San Francisco’s skyline under the Embarcadero are built on top of abandoned ships.

How many islands are in the Bay? 18 to 48 depending how you count.

Four times a day, the Bay rises and falls several feet with tides. At the highest tide, a quarter of the Bay’s volume—500 billion gallons—flows in and out of the Golden Gate. 

If you could drain all of the water out of the Bay, you’d see that the Bay floor is not flat. Powerful currents and tides sculpt ridges and valleys. People sculpt as well, dredging shipping channels and dumping debris—from tires to shopping carts to sunken ships and demolished buildings.