The hand-carved sandstone steps lead through the rainforest towards the bottom of the canyon. Tree ferns sieve the overhead light leaving the moss-fringed path in gloom. Far above tourists are sweltering through the summer crowds of the Blue Mountains’ ‘must-see’ tourist attractions, but here it is, cool and quiet, as Yasmin and I descend past dim grottos to the sound of trickling streams.

At the base of the canyon the track follows Greaves Creek downstream. The path passes through a dark tunnel formed by an ancient rock fall to emerge beside a 10-metre high waterfall, a delicate curtain of water drifting past the outstretched fronds of ferns. This area is known as the Grand Canyon. Over millions of years the creek has worn a narrow, meandering route through the soft sandstone, leaving towering cliffs of harder stone either side.

Three canyoners in wetsuits, helmets and head-torches prepare to lower themselves into the narrow chasm containing the creek. They adjust their harnesses, check ropes and test straps before abseiling some 20 metres to the level of the water to scramble, swim and slide downstream. I’d rather be walking – especially when it’s this spectacular.

We continue along a claystone ledge that winds around the side of the canyon beneath a deep rock overhang scoured out by ancient creek flows. Not far from the end of the overhang we break for lunch in a small clearing. We listen to the growl of thunder as we prepare our wraps.

Blue gum in the Grose Valley

The author compares his height with that of a grand old blue gum.

There are a few spots of rain which we ignore as we tuck into our food. Mistake. Within seconds the rain is belting down, turning my wrap to mush in my hands. By the time we’ve got coats and packcovers on we’re already soaked. Lightning flashes and the rain gets even harder as we dash back up the track towards the overhang, the track already awash with water.

We drop our packs in the shelter of the cave and watch the deluge in disbelief. The lip of the cave becomes a waterfall, a dancing wall of water sealing us from the outside world. There is nothing to do but put some warmer clothes on and make a cup of tea.

“I’m worried about those canyoners,” Yasmin says, pulling her scarf tight. “Isn’t this the kind of flash storm they’re always warning you about?”

Thunder booms. “They seemed pretty experienced,” I say, remembering the cool, professional way in which they tested their gear. But the water rushing towards the bottom of the canyon makes us increasingly worried, especially as there seems no way out except to get to the bottom of the slot.

Before we can fret any more, we see the grinning canyoners splashing up the track towards us, carrying their ropes and gear. “It’s exciting when it’s like that,” says the lead guy nonchalantly. “The water comes up quick. You just have to stay up high and keep on going.’” They squelch off along the wet path.

When the rain tapers to light drizzle we continue on our way. There’s no point trying to skirt puddles – the track is puddles – so we resign ourselves to wet shoes.

The lower section of the Grand Canyon looks remarkable after rain. The deluge has created a water-world of rushing streams, dripping green foliage and ephemeral waterfalls. Ahead a waterfall peels over a 25-metre high cliff trailing its gossamer threads into the creek below. Giant straight-trunked coachwood and sassafras trees stretch to reach the light beyond the canyon’s walls. The rain stops and a finger of sunshine presses into the canyon, intensifying the colours and releasing the smell of eucalypt and honey.

Reaching the junction with the track to Evan’s Lookout, we turn onto the Rodriguez Pass Walking Track, which continues beside Greaves Creek. (The Evans Lookout Track leads out of the canyon, concluding the popular Grand Canyon daywalk loop.)

The trail has been neatly swept clean of bark and leaf litter by the rushing passage of water that has proceeded us. The trail drops steeply and becomes rougher as we descend into the Grose Valley…

…The story continues in Wild issue 149, arriving in September. Subscribe today.