The "Family Restroom" on the basement floor of Bloomingdales in the Westfield mall is a single toilet lockable room, with a fairly irregular/low volume traffic pattern. It's hidden just behind the kids' clothing section (walk past the TV/game stations, take a right, and it's right in front of you, next to a water fountain.
What public restroom in San Francisco affords the most privacy to its users?
deano.com 