[ErroneousBosh]

I've done that and I've driven on the A9 hundreds if not thousands of times.

What's worse is that the inbuilt mapping in a lot of new cars think bits of it are 70mph dual carriageway when it's still single carriageway, and vice-versa.

[arethuza]

Same - driven up and down there countless times, but I still sometimes get alarmed on some of the dual carriageway parts where you can't see the other carriageway and I have a momentary panic of "This is a dual carriageway, isn't it?".