Mark and I climbed to the top of a hill in Tiburon. There was a clear view north towards the Richmond Bridge. At this time of year, the sun sets early, and soon it was getting darker and colder. Fog was coming in through the Golden Gate and spreading across the Bay, but the northern vista was still clear.
This is a stacked composite consisting of 15 exposures made with my 10.5mm digital fisheye lens. Each exposure was shot at 4 minutes, ISO 100, and f/5.6. The total elapsed exposure time was thus about an hour.
Note that with all the ambient light in the city sky, the star trails are not as bright as they are in a darker environment. For example, the stars seem very bright indeed in this version of Starry Night, which shows the Yosemite sky.
The green line across the foreground is a ferry boat that made its way into Larkspur during a couple of the exposures.