Canderwater was an interchange north of present junction 9, removed when the motorway was extended. This was an upgrade of the existing A74.
Road scheme and chronology data is courtesy SABRE (where much of it was gathered by member Ross Spur), with additional data from the UK Motorway Archive, the Scottish Roads Archive and the Northern Ireland Roads Site.
The second part of the story, where we learn why exactly the M4 gets narrower on the final approach to Europe’s biggest city.
The M4 into London was one of the UK's earliest and most ambitious motorway projects. It was bold, pioneering... and almost instantly regretted.
An introduction to what I write, and why I write it, and where my strange new road sign simulator fits in to all this.
Pictures taken as the first section of the M1 was being built in 1958-9, with all its unique architecture still under construction.
