Great mountain bike tracks all over NZ
I live in Auckland and most of our tracks are about 1 hour from the central city. Woodhill forest in west Auckland has a lot of single track devoted to moutain biking plus some jumps and obstacles set up - unforunately they now charge people to use it. Rotorua, in the middle of the North Island probably has some of the better tracks, also through forest and these ones you don't have to pay for. Our capital city, Wellington has a strong mountain bike community. More information can be found at http://www.mountainbike.co.nz/