Not a wall but during the Klondike Gold Rush when both Canada and the USA wanted to collect any revenues from gold miners both countries cut lines thru the forest between Washington and BC.... 100 years later you can still see those lines on google. In places you will see 3 lines. Canada cut 1, The USA cut 1, In compromise they often cut a 3rd line for clarity. These perfectly straight line run across the entire border between Alberta, BC and Washington, Idaho and a bit of Montana. All done before GPS or Logging Harvesters.
if you drive from Diablo, WA to Hope, BC, along Ross Lake, you will see that cut at the border up the mountains. Probably lots of other places too.