Twin Stream

A Selected Guide

The climbing at Twin Stream is on an impressive 800m high buttress of surprisingly solid greywacke, set amongst a cirque of two thousand metre mountains. Developed in the mid-nineties, the climbs are mostly long traditionally protected, multipitch routes that follow the quartz veined slabs, cracks and flakes, unique to Twin Stream. The buttress lies hidden from the Mount Cook road, at an elevation of 1400 metres, seven kilometres from the road bridge over Twin Stream.  Fortunately, the  Glentanner helicopter station allows a relatively cheap, five minute flight to the crag, saving time and energy for the excellent climbing.

Routes are often long with individual pitches of 40 metres or longer, the longest being over 200 metres. Most routes have bolted belays, allowing quick descents. Twin 60 metre ropes are ideal. For the longest pitches take a rack of 14 extendable draws, up to 10 cams and large selection of nuts and RPs. Even on bolted pitches take trad gear. For the bolted belays take a few metres of 6mm cord or similar, and perhaps a few maillons or old carabiners, to rig abseils on belays where there are no lower offs or rings on the bolts.

Newcomers to Twin Stream often encounter difficulties with either the walk in, the keas and katabatic winds that making camping noisy, or tricky route finding amongst the massive buttresses and gullies. This can be avoided by a fly-in walk-out approach, and by sleeping in the excellent bivy caves that provide a good nights sleep. Finally, and hopefully,  this guide will help you steer clear of major route finding issues.

For a successful trip begin with routes like Moon Rise, Moon Struck, Wily Spaniard, Peanut Slab, El Niño/Central Buttress, Centrefire, Aftershock, and Hungry Heart where not only is the climbing excellent but the access, protection and descents are relatively straightforward.

If you get up a few of these then you’ll be good to go. Other top picks are March Hare, Once We Were Wasters, Boy Germs, Pulp Friction, Blade Runner and Fibrillator. If its all too much just got for a nice walk instead

It goes without saying that Twin Stream is a serious mountain crag with all that entails, including the ability to route find, mange loose rock and self rescue or summon help in the event of an accident. There is patchy phone signal at points on the walk in and at higher points in the cirque.


Climbing at Twin Stream  began in the 1970s with Hugh Logan climbing with Paul Scaife and John Hobison. Development began in earnest in 1995 with the three pitch route 'Stealing a March' by Andy Macfarlane and John McCartney. Andy MacFarlane and Murray Judge became the main driving force over the next 6 years. Development has slowed in the last 15 years with only a few routes added to the impressive initial development. The potential for new routes remains huge, ranging from easy trad climbs to hard technical walls, often hundreds of metres long.

The skiing and winter climbing at Twin Stream is worthy of note. With a fly in and high drop-off excellent ski descents of Mount Dark and Kai Tarau can be had. Steep skiing is found in Shindig Gully and on surrounding couloirs. It is feasible to fly in and ski multiple lines and walk out in a day. Ice does form but not in such quantities as Bush Stream. In the right conditions though, there is much potential for ice and mixed routes.

The approach is in red, the descent from the top of the buttresss is in green. Red dots and arrows are helicopter landing sites for skiing


Access begins at the road bridge over Twin Stream, a 20 minute drive south of Mount Cook Village on the Twizel to Mount Cook road. Flying in and walking out is highly recommended, thus avoiding the 4 hour walk-in that involves 800m gain on indistinct sheep tracks and river bed.

Glentanner Park Helicopter Line is situated a few hundred meters from the start of the walk and as of 2021, up to 5 can fly in for about $360. Ask to be dropped off at the Twin Stream camp site.

If you do decide to walk in, the track starts on the true right of the road bridge. Occasional red/white markers and cairns mark the way which stays on the true right the whole way. Initially follow the river bed for 10 minutes then follow cairns onto the terrace. A vague track then ascends the left hand spur to reach the higher terrace.

Follow sheep tracks and markers through the matagouri until reaching a large eroded gut after 90 minutes. Cross this and again follow markers and indistinct path for a further 30 minutes until cairns mark a 10m decent to the flat river bed.

Then boulder hop for a further 1-2 hours, finally reaching the large flat camping area beneath the dramatic Central Buttress. Expect to get lost at various points. As an alternative, the river bed has been followed for the whole way thus avoiding the terraces.

The walk out, even if you lose the track, is much easier and takes two and half hours.

An excellent (although difficult to find) rock bivouac can be found at the far end of the meadow, 50m above the flats, on the true left, in the large rocks beneath Central Buttress. There is a flat balcony rock at the entrance. It accommodates 2 comfortably, 3 at a push. There are another two good bivys in the rocks below this, accomodating two in each. Aside from the advantage of not needing to carry a tent, it avoids the katabatic winds and keas that make camping noisy. There are multiple other less weather-proof rock bivouacs that require a bivy bag.

If camping, the keas will attack unoccupied tents so gear needs to be stashed during the day. Keas are endangered so tolerate their brazenness and don’t feed them. It goes without saying, carry out all rubbish.

With regrds the photo topos- please excuse the childish annotations. Red crosses are a double bolt belay, red circle is a trad belay, green circles are best descent routes- you can rap of anything but these are generally the most straightforward way down. Additional bolts are not always marked - refer to the old guide.

Below is a selected guide that so far contains about half of Twin Streams 90 routes, and should be used in conjunction with the old NZ Alpine Club Guide for Barron Saddle to Mount Brewster, and the website climbnz

I will add to this site over time.

The top pitches of the Southerly Front Slabs with Kai Tarau (2542m) behind.



Moonrise, a common starter route, is two pitches and relatively easy to find. Walk up to the bottom of the buttress and follow it left up scree slopes for about 30 minutes. It cannot be seen from the campsite. Walk off to the left or rap. Gives access to the massive slabs routes of Southerly Front.

A Moonrise 16, 17 follow the line of bolts

B Moonstruck 17, 17 * two bolts at the top of the first pitch

C Titan 19

D Moonshine Buttress 16, 15 *

E  Reservoir Chocks 16, 17 80m. Can be used as a direct start to Pulp Friction and the Southerly Front Slabs. Starts at the base of a wide chimney on the way up to Half Moon slabs. The first pitch is protected by prominent chockstones, belay from the broken ledges. Don't forget your micro wires for the second pitch, a good rock spike belay at the top allows a rap back down or continue directly onto the massive Southerly Front wall. A further thread rappel can be found on the small butress as shown.

F Pulp Friction


An absolutely stunning wall which can be accessed by walking along a fun ledge that begins behind and to the left of Half Moon Slabs. Alternatively, climb routes on Half Moon Slabs; or for a really big day climb The Lost Boys (5 pitches) or The Big Picture (4 pitches).


Gomers Go Round 18, 17, 17. Somewhere left of the slab, climbed to gain access for bolting. Not shown.

Gomers Go To Ground 24 ** Fine slab climbing left of the first pitch of Pulp Friction. 3 bolts to first belay of Pulp Friction. Not shown.

A Fully Wired 22, 20. Climb the first pitch of Pulp Friction or Gomers Go to Ground.  Traverse 3m  left from the first belay then up to bolt. Through bulge. 5 bolts to belay. Then straight up past 2 bolts to grassy cracks then move right to third belay of Pulp Friction

B Pulp Friction ** 19, 20, 19, 17, 13, 16. Straight up the centre of the slab. Amazing first pitch on perfect rock, 7 bolts. The next two pitches are almost as good, 11 bolts and 5 bolts respectively.

C Ground Hog Day 17, 19, 20. Climb the first pitch of Southerly Front, continue up to shallow pillar, belay on a flake. 7 bolts. P2 climb the pillar to a quick pull onto the upper slab and up to belay ledge, 6 bolts. P3 traverse left across the slab to the left edge and up. 7 bolts.

D Southerly Front 17, 20, 23, 23, 18, 15 ***. The first four pitches of Southerly Front took a week to put up because of the need to make fequent runs back to Mount Cook to recharge the six volt battery used to drill the ultra hard greywacke. Andy Mafarlane endured a thirteen metre whipper on the fourth crux pitch during the first ascent. Start below the large chockstone, climb the shallow pillar to a horizontal break and traverse left to the belay. Three pitches up the right hand slab to the ledge below the headwall.

E  Sticky Date Pudding 24, 24. Two long pitches to the right of Southerly Front

F Rock Vandals *.Two pitches on the right of the white corner. Grades 20, 22 to the ledge, climb the upper wall on natural gear. Grade 14, 16 to bolt belays.

G The Western World* 21, 22

H Stealing a March 16, 17, 18. The climb that started modern development of the crag. "Andy Macfarlane was on the phone, excited: I’ve just seen the biggest unclimbed slab in Australasia and we’re going to put a route up the middle of it." Dave Brash, New Zealand Alpine Journal, 2001. From the valley scree climb a broken rock pillar (the right hand of the three pillars) to the base of Southerly Front slabs. The broken rib leads to a groove left of the arête, higher up traverse right around the arête to a thin crack on the upper wall.

I March Hare 17, 18, 17, ***. Three excellent pitches up the arête, grades 17, 18, 17. Great position and exposure at the grade – a must.

J Forced March * 18, 20

K Unnamed 18

L Corner Chimney 15

M Splitting Hares 16, 17

Southerly Front Slabs



A Secrets and Lies 21. 11 bolts

B Stone Showers 14, 17. Descend by abseiling Wily Spaniard, or scramble off left along the ledges.

C Peanut Slab 19 *. Recognisable line of 6 bolts. Take gear.

D Wily Spaniard  15, 19, 17 **. Lovely trad crack to trad anchor on ledge. Step right onto slab clipping two bolts, heading right to a flake, then up, aiming to pass overhang on left. A long classic pitch. Semi hanging belay. P3 Up to ledges. Left hand line on pitch 2 is My Evil Twin 20.

E Fault Line 12, 20, 20. Up large blocks to ledge below overhang. P2 step left to break through roof, 5 bolts. P3 right hand line is 20, 7 bolts. Straight up is 23, 7 bolts. Bold in places.

F Once Were Wasters 18, 21 **. Left slanting slab to semi-hanging belay. Up corner and right to hyperclassic flakes.

G Rock Wren 24. Starts at El Niño. 7 bolts.

H El Niño first pitch. See Central Buttress below for full route description

I Swing In 24. Abseil from the top of Once were Wasters to start. Past 3 bolts. 

J Slab it to Me 19. Abseil to strart, follow flakes.

K South of the Border ** 21, 20, 20. Stunning and sustained from start to finish on occasionally friable rock

L Feathered Friends 20, 18, 18 **. Pull through overlap then leftwards through wide crack to belay, 3 bolts. Follow jugs left of the overhang, 2 bolts. Continue up.


Central Buttress Left Side


Sits directly above the bivy rocks- marked in black.

A Lost Boys 12, 20, 20, see Central Buttress Left Side

B Once Were Wasters 18, 21 ***, see Central Butress Left Side

C El Nino 16*, 5 pitches, best line shares pitches 2,3 and 5 with Central Buttress, the the right hand line on pitch 1 is Central Butress pitch 1

P1 4 bolts Start at an unstable looking triangular block on the left of the arete, it actually feels very solid when you’re standing on it. The initial gear looks bad but it is all there until the bolt on the arete. Get round the arete then for El Niño (16) go up just right of the arete on occasional bolts as marked. For the crux at 2/3 height there’s a sneaky bolt left around the arete on the next door route Rock Wren.

P2 is short, about 20m (14). Leave the right facing corner, up the slab a little boldly heading right around the little overhang. The next belay bolts are easily missed.

P3 ** A long excellent pitch (15) throughto the terrace.

P4 12* 50m Start a few yards left of the arete, up and head right underneath the overhang to belay

P5 15 up and left up to the arete and to the tilted belay slab.

The abseil is tricky to find. It’s at the lookers left end of the tilted slab. 2 bolts cunningly hidden on a scary looking small block with the abyss below. Second rap is at the right end of a ledge 50m down. This will take you down to the terrace where you can walk round to the El Niño line and rap that. Quite a long day out.

Central Buttress 17*, 8 bolts. Same start as El Niño then once on the arete keep traversing horizontally to line of bolts. Then join pitch 2 of El Niño.

D Jumbo Burger 18*, 7 bolts classic friction climbing

E Dial a Pizza 21, 7 bolts

F South of the Border ***see Central Buttress Left 

G Feathered Friends *** see Central Buttress Left

H 12**, pitch 4 of El Niño, see above 

I 17, 3 bolts, pitch 4 of Central Buttress

J Marigold 16, follow stepped flakes

Central Buttress



Shindig Gully is a stunning couloir with an impressive right hand wall. To get there walk down to where the river leaves the camping flats, then head up and right across scree slopes and an unstable gut. Be careful not to end up in the grotty gully right of Siberia wall, you’ve not gone far enough right if you end up in there. Takes 40 minutes. Keep going up and surmount the gully sized chockstone to access Aftershock and Centrefire, then a little further up to get to Hungry Heart, Fibrillator and Boy Germs.

A Steerpike 19, 17, 19 ** Gain starting ledges via left to right diagonal. Then aim for immaculate leaning corner with roof near top. Pitch 1 up thin crack and small corner to gain main corner. Second pitch - up corner, step right, gain crack line above roof to trad anchor. Then to arete, descend this to Aftershock anchor.

B Superconnector 15, 17, 14 Thin hand crack up and left of the orange wall then up the corner above. Move onto arete at the top of the corner 

C Chimney Sweep 15, 18, 16

D Aftershock 17, 17, 18 ** Lovely climbing. Looks gearless from the deck but there is plenty in horizontal breaks and 3 bolts. Head up to the little alcove belay which is a difficult to spot from the deck. Continue up, 5 bolts. Then head left and up to abseil anchors from second belay, 2 bolts. Second pitch right hand line is You be the Judge 23,  5 bolts. Same second belay, then directly up corner to top 3 bolts. Descend 

E Art for Arts Sake. 20, 21, line between Centrefire and Aftershock. 2 pitches, second pitch not marked.

F Centrefire 17,19, 20 *** Awesome second pitch. Start about 20m down from the Aftershock starting ledge. Either belay at a bolt below the first roof or better, go through the roof (well protected) and make a trad anchor in solid cracks above. The second pitch goes up the obvious cracks. The gear is perfect. The third pitch is a diabolical single move off the belay. French free it/stand in a sling then easy to the top. Descend down Aftershock. Three abseils. 

G A Big Day Out 17, 19, 13 Loose and bold second pitch

Shindig Gully



A Fibrillator 22, 19 *** The first pitch is a classic, sustained thin edges, 13 bolts. Head  left from the belay and up through overlaps, 9 bolts

B Hungry Hearts. ** 16, 15, 15, 15.First three pitches marked. Find Fibrillator then walk right. Spot a high single bolt on a triangular wall with a left facing corner on the right. You should be able to see the second bolt from the deck.  Climb up, clip the first bolt, head right a metre or two, place gear then step left up onto an improbable looking hand traverse which is straightforward. (If you keep heading right from the first bolt you’ll end up on Boygerms- a full 50m trad pitch). Then easily up to the third pitch which is a cracker. Finish after 3 pitches on lunch time ledge or do the final 15 pitch. Best descent from the ledge is down Fibrillator - the first abseil is off a hole in the rock piece of tat and a bolt. You’ll know it when you see it. Use your prussiks. 

C Boygerms 20 ** Well protected mega pitch. Climb the first section of Hungry Hearts as described above then trad belay on the pedastal at about 8m to avoid rope drag. Place sling to abseil off block. 

Approaching the crux of Fibrillator

Shindig Gully Upper


A-Moonrise B-Pulp Friction C-March Hare D-The Big Picture E-Peanut Slab F-Wily Spaniard G-Once Were Wasters H-El Nino I-Fibrillator J-Boygerms K-Centrefire L-Blade Runner

Pitch 4 El Niño (12)

The bivy

Fibrillator to the right. The 200m buttress is foreshortened.

Typical bolted belay. Bring tat and get creative.

The death block at the start of El Niño/Central Buttress

Blade Runner (22)

Skiing Shindig Gully

On the ledge above Wily Spaniard. Unclimbed rock above.

Shindig Gully

Pitch 2 Wily Spaniard

Late winter conditions Wingers wall/Siberia with potential winter routes

Pitch 2 Hungry Hearts

Taking Liberties. 600m grade 11. An interesting scramble with spectacular positions involving two pitches of easy but exposed climbing. Follow the terrace above Half Moon Slab, past the Southerly Front Slabs until the terrace ends. Avoid the chockstone gully and instead climb a 30m v-groove (8) to its left. This leads to a large central gully. Scramble easily up for about 200m. Where the gully steepens to a tower climb up and left, following a narrow terrace into an exposed position above a huge rotten gully. Climb through big chockstones regaining the tower (crux). Follow the cheval and ledges heading left before ascending the final tower. Abseil or down climb 30m to the top of Shindig Gully. Best descent is to walk to the road, heading east via peak 2155m, to the weather station and 4wd track. Descending the upper parts of Shindig Gully in summer does not look pleasant. E Cameron, March 2020.

Pitch 2 Fibrillator