Drivers baffled by "cryptic" national speed limit sign

A Reddit post with a photo of an inscrutable road sign is causing a ruckus. The original poster said, "I'm sure 99% of drivers don't know what this sign means," and the comments seem to bear out this claim.

The post, which received over 1,800 upvotes on the r/drivingUK subreddit, features an image of the UK's national speed limit sign — a white circular sign with a black diagonal stripe.

Many commenters expressed frustration with drivers who seem unaware that the sign indicates the national speed limit applies, which is 60 mph on single carriageways and 70 mph on dual carriageways for most vehicles.

Others noted the sign can be confusing, especially for foreign visitors unfamiliar with UK road rules. "If you're unfamiliar with it (e.g. a foreign driver), how are you supposed to guess it's the national speed limit?" one commenter wrote.

Some of the best comments:

"Drive diagonally?"
"Easy, it means you are now on the autobahn"
"In Cornwall it's usually a dare to do 60mph along an unclassified road, covered in mud or manure where the road is just over 2metres wide in some places"
"Flat-head screwdriver required?"
"Sir, this is r/drivingUK. 99% of members not only don't know what road signs mean; they passionately don't care."
"Go faster stripe"
"Pah! This one's easy. It means there are zebras grazing in the area."
"Emmm is it a speed camera"
"Some sort of pokéball"
"Miss world pageant ahead?"
"Aspirin? Paracetamol?"
"Typical speed limit applies. Which is confusing"
"Caution, flat-head screws on the road."
"Black belt ahead?"
"It's a sign for refugees?"
"Liquorice ahead, obviously."
"Safe to start looking for dogging sites?"
"Round liquorice allsorts?"
"Trebor mints forbidden"

And my favorite:

"Narrow bridge over an endless pit"

In all seriousness, why not just post the speed limit as a number?

Previously:
Gallery of confusing signs and designs
15-foot tall stack of confusing parking notices reduced by half
In effort to boost ticket revenue, LA deploys even more confusing parking signs
Citizen city-planner puts up ad-hoc street-sign