The A40 hasn't always terminated on that roundabout - it used to go up Station Hill, then turn right along Quay Road and end at the hotel by the Harbour station. Traffic for the ferry then had to cross the railway line, but that part of the road was unclassified. Access to the ferry has been drastically changed since then, and it makes sense for it to end where it does now, but let's not forget the full history.
Fascinating run through, but a bit of a pity you glossed over the twenty miles or so from Denham to Stokenchurch- it's a pretty important east-west route for local traffic in south Bucks! Especially if like me you have to sit on it in traffic every day in East Wycombe to get to one of the many business parks on it! Way too many lights installed and roundabouts removed!
Also there's a big project in High Wycombe to redirect the A40 from a 1960s flyover in the town centre to an alternative route, allowing the flyover to eventually be demolished. Someday anyway!
Fascinating and very informative. Never would have thought St Paul's, more like Edgware Road/Marylebone junction as the start
Definitely will be ready to read more of these as they come on line. Thanks again for a great site