Mile Rocks Light, Maritime lighthouse near Golden Gate Bridge, San Francisco, US

Mile Rocks Lighthouse is a maritime light station built on a reinforced concrete base, standing about 1 mile southwest of the Golden Gate Bridge on a small rocky outcrop. The structure guides ships through this busy shipping channel where strong currents and rocky hazards pose navigation challenges.

A bell buoy placed at the rocks in 1889 proved unreliable, pulled under by the currents. After the SS City of Rio de Janeiro struck the rocks in fog on 22 February 1901 and 128 of the 209 aboard died, Congress funded a lighthouse; contractor James McMahon began work in September 1904 and the light entered service in 1906.

The structure represents early maritime navigation methods along the California coast, with its original Fresnel lens now displayed at Old Point Loma Lighthouse.

This automated light station operates continuously and is visible from several coastal viewing areas and walking paths in San Francisco. The best views come from shore-based vantage points, especially on clear days when you can see both the lighthouse and the bridge.

The foundation sits on a small rocky formation that measures only about 40 feet wide at high tide, requiring innovative engineering solutions during construction. The original Fresnel lens was transferred to another lighthouse facility where it remains on public display.