State Highway 6 , the gateway to Queenstown. AKA the Devil's Staircase.
As a kid this road was gravel, and very scarey to a young muggle Annielin. I used to lie down in the back of the Singer Vogue from Kingston until we got to Frankton. I wasnt very brave indeed. No looking out of the window for me.
Thankfully the road has improved, although Transit NZ could do with opening its bank accounts and spending some money on a very well used road.
As this is a tourist hotspot, please be aware of traffic flow can be very heavy, and also the drivers not conversant with all road rules Kiwi.
But in saying that, there is safe options to park your RV, 4WD,Rental car, or family wagon/ Broomstick or Bicycle.