OK everyone, I think we may have all been wrong on this one apart from Chris, and Jeremy Clarkson of course.
I have just looked up the very luxurious Grove Hotel and Golf Club which just 2 miles from Chris's house right middle of Hertfordshire, and look, there is a huge great mountain range just behind their golf course! So Chris, what you need to do is set your sat nav for The Grove (WD17 3NL) and from there you should be able to find some fantastic mountain roads to explore!
Just don't forget to take your Kendal Mint Cake.