The Skippers Canyon road outside Queenstown in the South Island was earlier this year listed as one of the 22 most dangerous in the world. Driving Experiences, a UK based company, gave the road a fear factor of 7 out of 10.
Rental car terms and conditions specifically state that rental vehicles are not allowed on New Zealand beaches and the Skippers Canyon Road.
This NZ Harold article has a pretty nice photo (much better than my own).
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