New Zealand's Northern Explorer scenic rail journey, which starts in the country's largest city, Auckland, and ends at the capital Wellington, 420 miles away. The route required construction of numerous structures including long bridges to enable the train to ascend to the volcanic plateau, famed for its distinctive landscapes featuring active volcanoes amid the desert and pasture lands.

The first episode follows two rail routes on South Island, the spectacular Coastal Pacific running through the hills and vineyards of Marlborough to the small coastal town Kaikoura, and the TranzAlpine, crossing the Canterbury Plains towards the Southern Alps and Arthur's Pass National Park.