As any San Franciscan worth his salt-water taffy knows, Filbert (between Hyde and Leavenworth) is the steepest street in the city.
Ah, but is it?
According to the San Francisco Citizen blog, 22nd Street (between Church and Vicksburg) is exactly the same grade, 31.5 percent. So I guess the two streets are actually tied.
Now I have fodder to correct people the next time this comes up. Kind of like when people say that Lombard is the crookedest street in San Francisco (it's actually Vermont Street), or claim that Mark Twain said that the coldest winter he ever spent was a summer in San Francisco (it's wrongly attributed to him), or that the Jonestown cult drank Kool-Aid instead of...well, you know.
Correcting people is awesome!