New Zealand has a unique railsystem, that covers many parts of the two main islands.
Most of the track is for diesel engines only. Some track on the North Island is electrified, especially the rails of the metro link of Wellington and a bit trough the mountains north of Wellington.
Most of the track is 1067mm wide.
The biggest part of the traffic is on the main lines between Auckland and Wellington and Picton to Christchurch. In addition there is some passenger tourist travel between Christchurch and Greymouth (Trans Alpine) and in 2000 there has been passanger travel from Christchurch over Dunedin to Invercargill in the south (Southerner). As I know this train endet service in 2002.
On both island is a lot of heavy freight traffic. For instance coal in the western part of the south island, wood transport in eastern parts of the north and a lot of intermodal and container transport on both islands using the ferry link between Wellington and Picton.
Very interesting for tourists are the many railway museums and tourist railways on both islands.
The following pictures are taken on my 3-month-bicycle-tour in the years 1999 and 2000 (german only at the moment), where I saw a lot of trains and could take some pictures in different places. Down on the page you will find some usefull links to railway sites about and in New Zealand, enoy it.