Arthur's Pass is the middle of the three road crossings of New Zealand's Southern Alps, carrying State Highway 73 between Christchurch on the east coast and the West Coast near Greymouth. The pass itself sits at 920 m (3,020 ft), and the defining piece of riding is the Otira Viaduct on the western side — a 440 m bridge on a 12% grade that replaced one of the worst stretches of road in the country. It is open year-round but closes in snow, and the practical riding season is roughly October to April.
The shape of the crossing
Ridden west to east, SH 73 starts at Kumara Junction about 11 km south of Greymouth, runs inland through farmland and forest, then follows the Taramakau River up its valley to Otira. From Otira the road immediately does the interesting part: it crosses the river and climbs the Otira Gorge on the viaduct, up 495 m of altitude in a short distance, to the pass at 920 m. Then it drops gently to Arthur's Pass village at 740 m.
East of the village the road runs down the Bealey River valley, crosses the Waimakariri, and opens into the wide tussock and lake country around Cass, Lakes Grasmere and Pearson, and the limestone outcrops of Castle Hill. Then it climbs again, past Lake Lyndon, to Porters Pass at 939 m — which is, quietly, the highest point on the whole road, higher than Arthur's Pass itself. From Porters the descent drops into the Kowai valley to Springfield and out onto the flat Canterbury Plains for the run into Christchurch.
That gives you two distinct halves. West of the divide is rainforest, gorge and hard-won engineering. East is dry, open, big-sky high country. Very few crossings anywhere change character that completely in 150 km.
Route at a glance
| Route | State Highway 73, Christchurch to Kumara Junction near Greymouth |
| Arthur's Pass summit | 920 m (3,020 ft) |
| Highest point on the road | Porters Pass, 939 m (3,081 ft) |
| Arthur's Pass village | 740 m, 153 km from Christchurch, about a two-hour drive |
| Otira Viaduct | 440 m long, four spans, average 12% grade, opened 1999 |
| Western descent | 495 m of altitude from the summit down to Otira |
| Season | Open year-round, closures in winter snow at both Porters Pass and Arthur's Pass |
Open the Christchurch to Greymouth crossing in Google Maps — the full SH 73 route over the pass, ready to send to your navigation.
The Otira Viaduct and what it replaced
Before 1999 the road down to Otira ran on scree slopes that kept giving way. The section around Candy's Bend, Starvation Point and the Zig Zag was among the most dangerous highway in the country, closed regularly by slips and avalanches, and the subject of study after study. The answer, built between 1997 and 1999, was to take the road off the slope entirely.
The result is a four-span cantilever bridge, 440 m (1,440 ft) long, with piers about 40 m high standing on excavated cylinders four metres across and 30 metres deep. The deck averages a 12% grade. It is one of the few pieces of road engineering that reads as dramatic from the saddle rather than from a photograph — you come over the top, the mountains open out, and the road ahead is visibly hanging in the air.
There is a lookout at the top with parking, and it is worth the stop. Below the viaduct, the old coach road history is still visible in places: the 1866 route through the gorge had eleven bridges and five full 360-degree bends, and men drowned building it in a valley that receives between 4,000 and 7,000 mm of rain a year. That rainfall figure is the single most useful number for planning a ride here.
Porters Pass, the one nobody talks about
Arthur's Pass gets the name and the national park, but Porters Pass at 939 m is the higher of the two and the highest point on SH 73. It sits inside Korowai/Torlesse Tussocklands Park near Lake Lyndon, and it is the third-highest point on the South Island's state highway network, behind only the Lindis Pass and the Milford Road — and just one metre lower than the Milford Road at that.
For a rider it is the better corner sequence of the two. The eastern approach from Springfield climbs quickly out of the plains with a decent rhythm to it, and the view back down over the Canterbury Plains from near the top is the reward. It is also the section most likely to be icy first thing on a spring morning, because it faces the wrong way and sits high in dry, cold air.
The eastern high country
Between the village and Porters Pass the road runs through the section most riders remember afterwards without being able to name it. It follows the Bealey valley, crosses the Waimakariri on the Bealey Bridge, then runs along a bluff and out into open country past Lakes Grasmere and Pearson and the limestone outcrops around Castle Hill. It is fast, wide-open riding with long sightlines, tussock on both sides and mountains stacked up behind.
The history in this valley is worth a stop. The route was known to Māori for centuries as a pounamu trading corridor before Arthur Dudley Dobson crossed it in 1864, and a road through to Hokitika was complete by 1866, with Cobb & Co coaches running for the gold rush. The Midland railway line beside the road took until 1923 to finish, when the Otira Tunnel finally punched through the divide and ended the coach era. The village exists because it was the construction camp for that tunnel. In 1929 a magnitude 7.1 earthquake shook the pass, closing the road west for months.
Season, weather and practical detail
Season. As of August 2026, SH 73 is a year-round highway with no fixed seasonal closure, but both Porters Pass and Arthur's Pass are subject to frequent closures during winter snow. In the southern hemisphere that means the difficult months are roughly June to September, and the comfortable riding window is October to April. Check the official journey planner for road status and any chain requirement on the morning you ride, and check it again if the forecast has anything alpine in it.
Weather. The park is described by the Department of Conservation as rugged and mountainous with weather that changes rapidly and with little warning. Riders should be equipped for cold and wet even in high summer. The west side is temperate rainforest; the east side can be dry and 15 degrees warmer on the same afternoon.
Fuel and services. Arthur's Pass village has a petrol station, a general store, tea rooms and accommodation, and it is the only meaningful stop in the middle of the crossing. Springfield to the east and Otira to the west are the next options. Fill up before the alpine section rather than after it.
Road furniture. There are single-lane bridges north of Springfield. New Zealand's convention is that the sign shows which direction has priority — a large arrow means you go, a small one means you give way. Take it seriously; these are used at speed by locals.
Kea. The alpine parrots at the pass and the viaduct lookout are protected, endangered and enthusiastic about rubber and soft luggage. Do not feed them, and do not leave a bike unattended with straps or seat covers exposed.
Gear notes for Arthur's Pass
The crossing itself is straightforward to navigate — it is one highway. The planning problem is what you attach to it, because the obvious ride is a loop rather than an out-and-back, and the alternatives involve the Lewis Pass to the north or the long West Coast run south. Putting that loop together properly with a route planning workflow that survives a dead zone matters more here than the pass itself, since mobile coverage between Springfield and Otira is intermittent and disappears in the gorge.
Weather is the other thing worth preparing for. Riding from 4,000 mm of West Coast rainfall to dry Canterbury tussock in one afternoon means large temperature and surface swings, and a bike that leaves Greymouth warm arrives at Porters Pass cold. A TPMS sensor catches the pressure drift that goes with that, and a pre-ride check is cheap insurance before a 495 m descent on a wet 12% grade. Riders on the JADO S6 keep the map and the pressure readout on one display rather than two.
Arthur's Pass is one of the anchor crossings on the South Island loop, and it makes a natural counterpart to the Milford Road further south.
FAQ
How high is Arthur's Pass?
The pass is 920 m (3,020 ft). The village, about five kilometres to the south, sits at 740 m. The highest point on the road is actually Porters Pass at 939 m, on the Canterbury side.
Is Arthur's Pass open in winter?
There is no fixed seasonal closure, but both Porters Pass and Arthur's Pass close regularly during winter snow, and conditions between June and September can be genuinely alpine. Check the official road status before you ride and treat October to April as the reliable window.
How long does the crossing take?
Christchurch to Arthur's Pass village is 153 km and about two hours; Greymouth to the village is around an hour and a half. Allow most of a day if you want to stop at the viaduct lookout and the walks around the village.
Is there fuel on the pass?
Arthur's Pass village has a petrol station, a store and food. It is the only reliable stop in the alpine section, so top up there rather than assuming something exists in Otira.
Which direction is better to ride?
West to east puts the Otira Viaduct in front of you as a climb, with the mountains opening up ahead. East to west gives you the viaduct as a descent, which is more dramatic and less forgiving in the wet. Most riders who do it once end up doing it both ways.
