Been to San Francisco many times, I lived in California for while. But of all the cities in the SF Bay Area I liked Santa Cruz the best.
The most interesting city I've ever seen was in a dream. The dream started - I was out in the woods, and I met this guy (he had dark hair, a mustache and was wearing a black leather jacket) - he said he wanted to show me something. We walked through this jungle like area for what seemed like hours, finally we came to a clearing - there was a lake and across the lake a city.
It appeared to be made of what looked like green glass - different shaped domes and tubes connecting them. He told me I was in the distant future ~40,000 years so, and that he wasn't going to stick with me anymore because he didn't want to reveal to me what he really looked like, and some other stuff that sounded to me like some kind of gibberish about horses? I felt this overwhelming sense of well-being just looking at this city, and the sunlight reflecting off of it.
But then after the guy left, I felt myself waking up. I tried to keep myself in the dream and quickly will myself over the lake into the city just so I could get to it before I woke up, but it got all foggy when I was about half way across the lake and I woke up.