The derelect WWII bunker on the hill beyond added a sense of something mysterious about this place.
The bunker is actually a WWII era "base end" station for the gun batteries that protected the Golden Gate,
mostly the 16" batteries on the Marin headlands, and South of the GG.
The bunker contained a telescopic sight that was trained on a enemy ship, and the bearing and speed were automatically sent by phone line to a plotting center,
where an advanced analog computer aimed the guns, which had a range of well over 20 miles.

The gull was a perfect addition to the image as it landed on the rock to see what I was up to.

Sadly, I have lost the original of this image...