SF Gate has a story up about street names, errors and a map that shows you where to find them.
You’ve probably happened on many.
Each time a sidewalk in the city is paved or repaved, third-party contractors hired by theDepartment of Public Works ready themselves to stamp the intersecting street names into the wet concrete. They arrange fist-sized metal letter stamps in a row, backward in both order and orientation, then flip the whole thing over and engrave the name for decades to come.
Occasionally, though, something goes awry. SEE THE FULL STORY.