Leaving Ashburton on Route 77, we pushed north through Methven and Windwhistle (you know we couldn't make that up) to Darfield, where we picked up Route 73, the Great Alpine Highway, which would take us all the way to the west coast.  Like yesterday, we saw thousands of gorse plants (pictured above), very noticeable at this time of year because of their brilliant yellow blooms.  Introduced as ornamental hedges by Europeans in the very early settlement stages of New Zealand, the plant spread rapidly in the country's temperate climate.  Today it is considered a major invasive species due to its aggressive seed dispersal.  Millions of dollars have been spent trying to control it. Unfortunately, the very methods most useful in removing the noxious weed are also effective at spreading its seed.
The Great Alpine Highway bisects Arthur's Pass National Park, which is centered on the mountain pass and the village of the same name.  Because it provides easy access to some treacherous mountain terrain, the park has developed an unfortunate and perhaps undeserved reputation as one of the most dangerous national parks in New Zealand. 

     

Rather than having a day's trek to ease into the mountains like other areas, the close proximity of extreme trails from the village has lured hikers in over their heads and has led to the deaths of adventurers who lacked the equipment and skill level for the terrain or found themselves trapped by rapidly changing weather.  As we passed through the village, we saw signs advertising free use of locator beacons for hikers.

Otira Viaduct

Driving through the pass was not particularly scenic, but on the western side, the engineering marvel of the Otira Viaduct was another story.  Completed in 1999, this four-span bridge carries traffic away from the rockslide-prone mountainside through the Otira River valley.  At just over a quarter-mile long, the viaduct sits on piers 131 feet above the valley floor.  A photo on the web site of Numa Hammers, which provided equipment for setting the piers, shows the road as it was before this modern improvement.

Frequently closed by avalanches and rockslides, the old road before the viaduct.

More engineering prowess just beyond the viaduct has further enhanced safety near the pass.  An aqueduct was installed to redirect the water from Reid Falls over the highway rather than onto it, followed by a rockslide shelter with a sloped roof that deflects landslides to the valley below.

Reid Falls takes a new course

Five miles past Otira we stopped to check out the Morrison Footbridge across the Otira River.  This bridge marks the beginning of a 15-mile mountain run course that is part of New Zealand's Coast-to-Coast race.  Top athletes complete the section in about three hours.  Most hikers take two days.

Morrison Footbridge

On the east side of the pass, most of the terrain had little vegetation other than short grasses and tussocky clumps.  Once we descended to the western side, we began to see thick forests, growing more lush as we neared the west coast.   By the time we reached our destination of Greymouth on the west coast, we were in a full-blown rain forest with tree-sized ferns and tangled undergrowth beneath looming palms and cabbage trees.  Tomorrow we plan to explore some spots north and south of Greymouth in search of some of New Zealand's coastal beauty.