Trivia: Longest road that doesn't touch a Motorway

[c2R]

That is an unexpected find!

[KeithW]

But it is listed in the index at the very top of the A259 wiki entry, under History, as "2.1 Dover – Pevensey"?

The A20 used to end on the A259, but because the majority of Dover traffic came from the Maidstone direction rather than Hastings they flipped the number beyond that point.

The Ten Mile Map for 1956 on Sabre Maps show the route to Dover as the A259, although the same titled map from N.L.S. show it as the A20, so the change must have been around then.

Fair enough. On the 1922-23 map it shows the A259 from Folkestone following what became the A20. At that time the main traffic between Folkestone and Dover would have been local. With RORO ferries not being in civilian use until after WW2 there would be no point in continuing on to Dover if you were in Folkestone. In fact most travellers would have caught the train which ran onto the pier at Folkestone Harbour Station where you simply walked from the train to the ferry while at Dover the rolling stock could be loaded onto the train ferry in the Western Docks.