"What's a guy my age doing here?" said Andy as he pulled himself up around another boulder. "At 55 you should be home reading a book instead of clambering over mountains," he muttered to himself.
Andy had done a fair amount of tramping in the past, spending almost every holiday in one or other of our national or forest parks. But none of that had ever prepared him for this.
Wow! From his perch on the Ball Ridge Andy's eyes swept the view: the Tasman Glacier from Lake Pukaki right up to Graham Saddle and around the corner to Hochstetter Dome.
And the back view was even more dramatic: the mighty Caroline Face of Mount Cook with ice avalanches thundering down periodically - just to put us puny mortals into perspective.
"Come on, Andy, we've got a long way to go!" coaxed Erica, our professional mountain guide. She was right - we had 850 metres to climb this day, up to Caroline Hut, our alpine refuge for two nights.
But with so much to look at both on a macro and a micro-scale Andy didn't mind taking longer than the usual six hours. Just too many distractions - mountain daisies and buttercups, cushion plants - to simply keep plodding on upwards. Erica knew her plants well too and was able to generate interest and enthusiasm in the less botanically-oriented members of the group.
As we progressed up the spur the pure white spire of Mount Tasman came into view, picturesquely framed through Cinerama Col. By now we really were feeling as though we were in the realm of mountaineers, so close to New Zealand's biggest mountains and yet still on tramping terrain.
Standing on Ball Ridge, it was only the Ball Glacier down there which separated us from the danger of those hanging ice-cliffs on the Caroline Face. Yet, apart from the guide, there were no mountaineers amongst us and Andy was by no means the oldest in the group.
Murray, in spite of his 69 years, was fitter than the young couple in their twenties!
As the ridge levelled off Caroline Hut became visible, camouflaged against the surrounding rocks. It was January and all the snow had disappeared from around the hut (apparently this hut gets completely buried in winter, sometimes three metres under!).
Erica entertained us with stories of having to use an avalanche probe to find the hut in spring and of the superhuman efforts to remove all those cubic metres of snow by means of chainsaw, shovels and runnels.
"Ah the ecstasy of bootless feet," sighed Murray stretching out on his bunk.
"You'll certainly be soleless if you walk any further in those boots tomorrow," quipped Erica, detecting a flapping sole.
She disappeared and returned shortly with a spare pair of boots. "See, just like Cinderella's slipper - of course they fit!" Nothing seemed to phase her, and she refused all help in the kitchen.
The rest of us drifted outside to watch the changing light playing on the amphitheatre of mountains.
"I just can't seem to fit Mount Cook into my camera frame," protested Susan. "It's too close!" As if to reinforce her remarks that you shouldn't try to "capture" Mount Cook, a huge ice avalanche roared down the Caroline Face again.
Despite her tastily prepared three-course dinner Erica had difficulty persuading us to leave the spectacle.
On the snow slope behind the hut next morning Erica's instructions were unmistakeably clear: "If you slip, you roll over onto your front and do a spider."
That meant with arms and legs spread out you push yourself up off the slope so that your bottom's up in the air. She insisted that everybody practise this self-arresting exercise several times until it became semi-automatic.
A lesson in using crampons and ice-axe ensued. "Ice-axe, one, two, ice-axe, one two. Erica ensured each member of the group had mastered the technique before proceeding up the ridge.
Andy and Murray especially couldn't resist the excitement of experimenting with a new toy and proudly exercised their fledgling mountaineering skills.
By now the sun was shining full-on to the Caroline Face, bringing the ice to life once more, in a glistening and cracking symphony.
We were weaving our way through rocks and across snowfields up towards Ball Pass. From the Pass we were to make a short detour to climb Kaitaki Peak (2222m), from which we were promised the classic view of the South Ridge of Mount Cook.
It all looked within reach and easy to climb, but even the Low Peak of Mount Cook was over 5000 feet above us. "Isn't it great to be alive!" "It's such a privilege to be here." "I would never have done this on my own..."
The summit comments were many and varied, but all underlined the adage that men can't move mountains, but mountains can move men (and women!).
A leisurely return to the hut and there was still time for a siesta for those who wanted it or more observation of the natural entertainment at the hut's back door - this time in the form of a couple of cheeky keas trying to peck out the screwnails on the toilet roof.
The third day was to be the big day - over the Pass and back to Mount Cook village. Andy was somewhat daunted by the prospect of nine hours on his feet, but Erica's experience with similar clients was able to reassure him.
"You haven't built up tramping stamina over all those years for nothing. - If we can get people in their seventies over this pass, we'll get you over."
From the Pass we looked down into the Hooker Valley. It looked steep, very steep. The snow was hard so crampons would be necessary and we would need to put our ice-axe, step, step rhythm into practice. Erica set up a fixed rope for us the attach ourselves to, just in case anybody slipped.
Below, apprehension gave way to smiles and a great sense of achievement, as we spread ourselves out on a large rock in the sun for morning tea. Still a long way to go, but the difficult part was over.
"Do we have to cross that scree over there?" asked Andy. "Yes, but if you look closely, you'll see that it's benched, " returned Erica.
Andy, somewhat overweight, did have some difficulties with this next section, when it came to clambering around or over the odd large boulder, but Murray just bounded over any obstacle like a chamois.
One last snow slope to descend before we reached a level area of snowgrass. The ideal lunch spot with Mount Sefton looming opposite, the Copland Pass, La Perouse and the South Face of Mount Cook now in view.
Dropping down through alpine herbfields we encountered masses of Ranunculus lyallii, the Mount Cook lily.
Glad to reach flat ground again, we took our time meandering down the Hooker Valley, enjoying waterfalls and refreshing pools. The luxuriance of the vegetation in the valley was familiar and reassuring, a contrast to the more rugged environment above.
But the mystique of that high alpine world would not be forgotten. "It has changed my life", wrote Andy after the trip.
As we approached the end of the Hooker Valley Erica turned and congratulated us on a successful traverse. It was she who needed to be congratulated.
As many times before she had proved that age is no barrier to meeting the challenge of a Ball Pass Crossing, and that those over 50 can enjoy a true alpine adventure with little or no mountaineering experience.