Along with probably having the fewest straight roads in the world (I read maps as a hobby, and the numerous town plans I've seen round the world are usually dominated by straight roads, in many of ours you're lucky to find more than one) it seems our road naming and numbering is equally disorganised. Though the Romans had the power to build the few long straight roads in the UK, since they left, local 'mafia' style landowners made sure the roads didn't use their land. Instead, they had to bend round it and back again, and even now the few new roads that get built are just the same.
Here are a couple of typically British 'Inconsiderate to users' road facts. Is this just something we have here, or are there any like this in other places? Please put any you know of here as well.

Barking Road, which links Barking in East London with Canning Town, starts its numbering at the Canning Town End. It then reaches 778 and guess what, it starts again at 1and keeps going to about 600. Admittedy the new run is all in the E6 postcode, but is it really a good idea to do this at all- not every visitor knows the postcode and I'm sure the residents regularly get people knocking for the 'other number 357' or whatever.

Many long roads change their names every mile or two. This is silly enough, but some change back to the same one later on.
Examples are Morden Road in Merton, that changes to Morden Hall Road. It continues into Morden, bears to the left at a roundabout, and then reverts back to Morden Road, Morden (as opposed to Merton). It then continues through Mitcham. This is on a 2 mile stretch of Road that runs through the 3 districts I mentioned.

The next is Park Road in Teddington. This becomes Sandy Lane, crossing into Hampton Wick. 1/4 of a mile later it reverts back to Park Road in Hampton Wick.

So far, I haven't found a road that has the same name twice in this fashion in the same district, but I doubt that if there was the council would bother to fix it. I will keep looking. In the USA, I saw main roads keep the same name for their whole length, and I remember one starting in Miami went on for something like 100 miles with one name. Maybe this is why the London taxi drivers have to take exams before qualifying.

I will add more anomalies if/when I remember them!

Well ... In the old centre of Norwich a few streets change name every 100-400 yards. Wow!

That's the old "meets and bounds" system in action. Once these delineators are established, it is impossible to change them into something coherent that a modern society can deal with. It worked fine in the 15th century.
I'm not criticizing, just observing, the system of roads that "just grew" from delineating land ownership based on where a tree grew, or a large rock was found, or a meandering stream flowed.

I've just been doing some research for my website when I was given this site, all about British roads.
It trumped my little anomalies with the B 1106 in Bury St Edmunds. It crosses a roundabout with another road of equal length (some miles) which is called the B 1106. They even have the map to prove it.