Port Jackson, Coromandel
Definitely worth doing especially if you want away from the crowds, I'm not saying its COMPLETELY isolated up here but it is pretty nice. I haven't done this walk in years but heres a photo of my Mum and her friend doing it. You can walk round the coast one way and back over the hills the other way or get someone to drive to pick you up - although you have to drive south a long way and then back up north a long way - not recommended unless your party plan to stay in Stony Bay after the walk.
If you are heading to Port Jackson when you get to the summit, stop to enjoy the spectacular views across the Colville Channel to Great Barrier Island with Channel Island in the foreground. At Port Jackson, you go through the gate at the DoC campground. THis is a good place to stay and you can set up your tent right on the beach front.
You can also continue along a road which clings to rugged cliff tops. Here the road ends at the DoC remote beach campsite and the beautiful Coromandel Walkway to Stony Bay begins. There is a backpackers here which is one of the most remote in NZ.
For a spectacular 3 hour walk, follow the walkway as far as the wooden seat overlooking the Pinnacles and Curvier Island.