Hi All. A bit of help please. I'll be arriving at SFO late on a Wednesday evening (21h30) and need to get to my O'Farrell Street hotel in Union Square. Now I have read all the previous posts about other questions similar to this, and I am quite happy to take the BART to Powell Street and walk, but Would it be safe walking at that time of night? Bear in mind that this will be a first timer in SF. Should I take the BART and get a taxi - can I get one at that time? Thanks