Last year I rode the BART from Oakland to Fremont. Like after midnight. I was constantly on guard.
I was so scared something like a shooting was going to happen. That's what I get growing up in the south bay suburbs.
EDIT: Just found a picture of the escalator. It doesn't even look dirty though.
LOL. The BART is fun if you are going to the right places and at the right time too. Midnight travel sounds a bit scary. I spent a summer in Berkeley and used the BART to visit San Francisco several times. It was great.
South Bay? I'm guessing Fremont? I went to high school in San Jose.