From what I can glean from viewing Images in Google, most of Wilkinson's poster work was done for the London, Midland and Scottish Railway between the world wars. The LMR's main routes were up the west side of Britain, so places such as the Lake District, Wales and Western Scotland were often featured in his work.
Not shown here are Wilkinson's naval paintings -- I might feature those in another post. For those, he used a painterly technique quite different from the areas of flat color he judged appropriate for poster work. A versatile professional, and good at what he did.