Some signs are useless. In addition, this one is dangerous too and it says so…
This sign says “CAUTION: This sign has sharp edges. Do not touch the edges of this sign.” Well, if the sign wasn’t there, then there wouldn’t be any sharp edges for us to touch. And there wouldn’t be a need for such a Caution.
Actually, I think the sign is about “no smoking”. See tiny icon in lower right. Not sure what is the icon on lower left indicate.
And the bottom text says “Also, the bridge is out ahead.” I guess, they thought the sharp edges of the sign is more important the a bridge being out.
This sign reminds me of another ironic sign linked here.