The gentle clackety-clack of track against wheel will be your constant companion on this trip. Beating a soothing rhythm as it meanders through the Arthur's Pass National Park, it's all part of the must-try TranzAlpine railway experience.
Deep gorges whiz by, with glimpses of clear mountain water rushing through wide shingle riverbeds below. Dark-green broom sits behind shaggy cinnamon-brown tussock, while snow-frosted mountains lord over the whole scene.
Arthur's Pass National Park is a place of contrasts, a stark beauty that is synonymous with being in the heart of the Southern Alps: dry beech forest in the east, luxuriant rainforest on the western slopes, and a historic highway and railway connecting the two.
Located in the middle of all this is Arthur's Pass village, a walker's and tramper's haven with both short walks and longer tramps that lead to the summits of nearby mountains.
More than 30 backcountry huts, linked by a large network of tracks, provide shelter within the park.
Birdlife is prolific. Look out for the kea, the endangered great spotted kiwi, bellbirds, fantails, wrybill and black-fronted tern, before descending through the rainforest to the West Coast town of Greymouth.
Relax and rediscover the uniqueness of train travel or self-drive and explore SH73 at your own pace.