Within the depths of the Academy of Sciences, there’s a tunnel called the Flooded Forest. People can sit there for hours and see all kinds of fish drifting overhead. It’s inspiring to see; no matter where you’re from or what language you speak, nature is fascinating for everyone. Larger version is viewable here.
Part of my commute involves BART, the main train system for the San Francisco Bay Area. Don’t be fooled by the lack of people; this was taken at the Embarcadero station on a Saturday. If I took this on a weekday evening, there’d be at least 500 more people in this photo.
The Stockton Street tunnel is just north of Union Square and is probably the least strenuous walking route to Chinatown. Don’t be fooled by the lack of people; depending on the hour you enter, you’ll face tons of traffic and hordes of schoolchildren.