I drove from Toronto to Montreal a couple of years ago. I got on the 401 and there was a large distance to the turn off. I've forgotten what it was but Google Maps suggests 450km.
I'd imagine some trips west on the Trans-Canada would give some 4 figure numbers.
A9 between Inverness and Perth gives about 105 miles with no sat-nav junctions. My old Tomtom gives 180 miles going south from Glasgow without advising a lane change, but newer ones advise a change when the M74 becomes the M6.