The Point Diablo Light is a lighthouse

Lighthouse

A lighthouse is a tower, building, or other type of structure designed to emit light from a system of lamps and lenses or, in older times, from a fire, and used as an aid to navigation for maritime pilots at sea or on inland waterways....

 in California

California

California is a state located on the West Coast of the United States. It is by far the most populous U.S. state, and the third-largest by land area...

,
United States

United States

The United States of America is a federal constitutional republic comprising fifty states and a federal district...

, about halfway between Point Bonita and Lime Point on the northern side of the Golden Gate Bridge

Golden Gate Bridge

The Golden Gate Bridge is a suspension bridge spanning the Golden Gate, the opening of the San Francisco Bay into the Pacific Ocean. As part of both U.S. Route 101 and California State Route 1, the structure links the city of San Francisco, on the northern tip of the San Francisco Peninsula, to...

, California

California

California is a state located on the West Coast of the United States. It is by far the most populous U.S. state, and the third-largest by land area...

History

In 1923, the Lighthouse Service decided to mark this navigational hazard, and a small white shack with a pitched red roof was placed on the sloping point some eighty feet above the water. An array of solar panels now powers the modern beacon positioned atop the shack.(per Lighthouse Friends)