Wheel Nut:
I would have thought as the white lines split, but it seems hypothetical, as Mr Vain said, you may not reach 50mph because of the bendy bits
In this case yes it’'s hypothetical, although I was just thinking about larger duals with a similar set up.
A dual carriageway is defined by what seperates the two opposing flows of traffic.
If the traffic is seperated by paint or plastic cones then it is not a dual.
Common error for truckers - a dual carriageway is contraflowed so that both flows have one lane each on the same side but seperated by plastic cones fitted into where the cats eyes were and a 50 limit is posted.
The speed limit for LGVs over 7.5 tonne in this situation is…
… 40
Well done those that got this right. 
Wheel Nut:
This one seems to confuse most people
Ah the A556 two lane single carriageway 
ROG:
Wheel Nut:
This one seems to confuse most peopleAh the A556 two lane single carriageway
Nah, it don’t confuse me. I remember the 4 lane single carriageway A77 .
I also remember 3 lane single carriageways used to be more common (the non-prioritised anything goes variety ), but they’ve either been prioritised or shrunk with hatching. 
More oddities HERE
macplaxton:
More oddities HERE
I like those - a good mix
going back to the origanal subject this dual carrige way was put in during the war so that RAF traffic could pass (from RAF Coltishall) they used to stack up there waiting for the convoy coming the other way to pass
I am no expert but my Grandfarther has lived in the village (Tunstead) where the dual carrige way is all his life
And yes as mentioned before it certainaly has seen its fair share of Santa Pod racing action not that I ever joined in 
I remember that most A roads were made into 3 lanes like several of the pictures, but with the attitude of modern drivers it would be carnage, no one will back off, no one is very polite on the roads anymore.
Because the Americans have to put hot liquid warnings on coffee cups and signs on dogs saying “this dog may bite”. We have become as stupid, unless there is a physical guide or barrier, many drivers will simply crash.
