I parked my car at a legal spot with a meter in downtown San Francisco around 11:30 PM and came back to my car around 2 AM. I saw NO signs of any street cleaning or signs saying that you can't park there. I came back and got a ticket for street cleaning at 1 AM. I searched google and can't find any information. I am going to protest this citation as there were no signs at all about street cleaning. For those familiar with SF street cleaning, does it really happen at 1 AM on a weekend night? If so, that is so screwed up. It was near Embarcadero center.