One for you numbering geeks...

I was writing up the rather convoluted history of the [[A4018]] and spotted something that makes me wonder if a few maps are wrong, or at least inaccurate. Let's quickly recap what we can see on the maps

1) MOT maps (1923 and 1926) - A4018 runs from Bristol to Avonmouth via Shirehampton
2) 1932 and 1934 Ten Mile - A4018 has turned into a B road
3) 1945 NPE - A4018 is back but only as far as Westbury Park

However, I reckon the Ten Miles are not correct. My reasoning is the 1935 Renumbering Documents, which include an entry for the B4470 described as "Bristol (Link at Westbury Park)" with the note "Renumbered as B4054 (Westbury Park Spur). Indicated at north west end as A4018 (chequer)". That kind of suggests a far more simpler case of affairs that the A4018 was cut back to here when the Portway opened, with the road ahead becoming B4470 for all of a few hundred yards, then an extension of the B4054 after that.

Anyone disagree?

Yes, me.

I've gone through a few non-OS sources, and I have a Newnes Atlas which is basically early 1940s mapping (Winchester Bypass shown; changes on the Isle of Wight, the Church Stretton and Worboys Bypasses not shown) and whilst the map of Bristol is right on the page fold, it clearly shows that the erstwhile A4018 is entirely a B-class road.

Meanwhile, my early 1950s Johnson and Bacon atles (which has all the aforementioned changes) shows the truncated A4018 on it.

Going slightly further back, my 1928 AA Members' Handbook shows the A4018 heading out of Bristol to the edge of the town plan.

Hmmm. I don't buy that. Here's my 1962 Newnes Atlas showing the same thing - and with Cribbs Causeway and the Severn Bridge under construction!

Maps, especially non OS ones, can always be wrong. Official MOT documentation sent out to regional authorities to tell them what should go on signs, is less likely to be so.

1948 AA Handbook shows this:

Which may or may not be of help! I have some OS maps downstairs, but my brother's on Skype, so I'll look later.

Yes, but what we have here is different mapping from different sources saying the same thing. There's no reason why there isn't a supplementary document from the MoT saying "actually lads, let's do this..."

Normally, I'd agree with your assessment, but the Ten Mile Road Maps are effectively MoT documentation in a way that the regular OS series aren't, and having another publisher say the same thing is, well, curious.

I think a possible judge on this would be a Fifth Edition map of Bristol. One exists, and hopefully it's dated before 1935. The British Library will have a copy.

I've had a look at my maps, and the oldest I have is the NPE for Bristol, 1930 with revisions to 1946. It shows what Ritchie describes above. I thought I'd got a 30s Barts half inch sheet somewhere, but I can't find it, and even if I have I suspect that the road will be coloured red (as many B roads are) without a number, so not much help, sorry

One obvious explanation for all of this could be that it did get downgraded to a B road (B4055?) in 1926, but then upgraded to an A road in 1934, after that year's Ten Mile Map was published, but before the 1935 renumbering memos were drafted out. Actually, isn't that around the time the Aust Ferry was upgraded to vehicle traffic? That might explain a slight increase in traffic demand to tip the Bristol - Westbury Park section of the route up to Class I status, after which, in the pre Cribbs Causeway to M5 era, things dispersed in various directions.