Compared to all the bridges in New York City, and much of the State of New York, I think the Golden Gate Bridge is the most awesome bridge in the United States and also very well maintained.
They night life is very active just like any major city in the USA, and if you go into San Fran don’t except people to be friendly. I recommend go to a not druggy bar or restaurant in Haight-Ashbury. San Fran is very cliquish directly related to the neighborhood you visit with a few supposed exceptions of neighborhoods.
I am glad they have something like the Cal-train, however, its very disappointing design considering so many hi-tech companies here, that is compared to Northern European train systems. Cal-train was expensive too, and sloooowwww.
I would use Cal-train quite a bit visiting San Francisco much, and not a single person would give me an (eye based) acknowledgement of my existence or their own. This of course was not true when I visited Oakland, in Oakland, people were more human, just like in NYC, regardless of their economic or academic standing. I have traveled a little bit over the world, and I always meet people where I could have conversations or a (true) friendly hello. The exception being was Stockholm, Sweden (however, I did meet friendly people in other parts of Sweden), and well you have to kind of speak their language too. I have found some people from the UK and Australia to be very friendly as I meet them in different parts of the world. I met an upper middle aged UK couple, and I had a tiny bit of conversation. She said to me “it’s a little strange, I have found nobody speaks to you here.” I nodded and said “Yes, that’s been my experience too.” However, when I was at a Bar and drinking more (beer) than I should have been (Haight Ashbury area) then I had made some friends for the night. San Francisco is still many decades behind in socialization, as everyone is so neighborhood conscious that one could say there is neighborhood based discrimination,and that is so funny. Outside of San Fran, including San Mateo, is much more friendlier, and you know what the Asians, and the Hispanics turned out to be the most friendliest, of course, almost everyone in Oakland was friendlier and had less of weird San-fran complex.