Fellas, the next time you’re looking to pull, try Joe’s approach. “He’s quite the Lothario around here,” my guide Max tells me. “Ladies swarm to his bachelor pad.”

Today it’s my turn. Kitted out in my most attractive gear – that’s boiler suit, helmet and harness – I start my descent into his boudoir. The light? Non-existent. The smell? Suspiciously like weed.

“That’s not marijuana you’re being wafted with. It’s urine,” Max says, flapping the air like a maniac. “That’s how Joe attracts the ladies.”

Joe may be a humble wild rat, but his home – known as the Rat’s Nest Cave – is quite a palace. Located in Western Canada’s Grotto Mountain, 50 miles from the city of Calgary, it’s a 4km spaghetti junction of passageways, and exploring its caves is just one part of the state of Alberta’s rich bounty of adventure activities. Sure, the Canadian Rockies – my home for the next seven days – may be most famous for their ski slopes, but when the snow melts, the fresh air and national parks are a playground for a Londoner trying to escape the drudgery of the city.

Today’s situation is a first. 16 storeys below ground it’s a cool 5°C – the ideal temperature for squeezing head-first through crevasses about the size of my calf. Leaving Joe’s intoxicating branches-and-bones nest behind, we breathe in, compress our chests, shrink our shoulders and continue slithering through the pitch black across damp sheets of limestone that have been given ominous names like ‘treacherous slab’, ‘laundry chute’ and ‘there will be monsters’.

an isolated forest trail gives way to a Narnia-esque scene of two aquamarine pools, lofty pines and a light smattering of snow

“Slide with one arm above your head, like Superman,” Max urges as I squeeze past animal bones and through a letterbox-sized space to the safety – and oxygen – of a barely man-height stalactite- and stalagmite-packed cavern. “It’ll make you slimmer.”

Any millimetres lost by awkward, claustrophobia-induced stretches are soon gained back in the natural light of Alberta province’s hippest town: Canmore; a place where the population is young, the burgers are hefty and the bloody marys are pimped (think vodka and Clamato, topped with a colourful parade of pickled garnishes – known as a Caesar).

Here, spectacular hiking trails litter the small, three-road town’s backstreets. Still quivering and bruised from caving, I ease my legs with a sluggish creep to Grassi Lakes, where an isolated forest trail gives way to a Narnia-esque scene of two aquamarine pools, lofty pines and a light smattering of snow. It’s breathtaking. The altitude is dizzying, yes – I live in a city 35m above sea level, after all – but the setting is, too, with colours so intense that my photos make me look like a healthy extra in an Abercrombie spring/summer fashion campaign. Hell, even the beer in this part of the world is wholesome – Grizzly Paw, the local brewery, crafts its nectar with glacial water from a nearby mountain.

And boy, do they do mountains here. Handily, driving through the region’s national parks is easy, and a must for flexibility as much as the epic views. A few hours further up the road from Canmore, I pull into the one-horse town of Lake Louise, one of several stop-off spots in Banff National Park. Town, it turns out, is a generous term, seeing as Lake Louise consists of a small parking lot, a post office (closed), a pub (open) and an off-licence (24-hour). You can’t fault Canadian priorities. But this small cluster of buildings is not the reason thousands of people flock to Lake Louise – the clue’s in the name. A few miles further on I see it, the subject of my latest Instagram obsession in all it’s dark-teal glory: a 2km long stretch of crystal-clear water cocooned in a valley of towering slabs of rock, dotted with forest. Way off in the distance I can make out the raw, creeping forms of six ancient glaciers.

It’s time to walk. At first the path is flat and narrow – a brisk trot along the pine tree-scattered shores in the company of dog walkers, selfie stick-wielders and squirrels. Then it gets serious; after a couple of kilometres I see the first warnings of potential danger: wooden signs plastered with dated snaps of bears – fur coiffed, ’80s-style, and with snarling teeth. Armed with my anti-grizzly devices – a bell and a can of bear spray – I push on above the treeline, the gentle slope becoming far less forgiving and the mountains looming, grey and ominous beneath a moody sky.

Few bother to make it this far up the mountain trail, but those who do are rewarded. Clambering on towards the Abbot’s Pass viewpoint – a thin ridge of crumbling, steel-coloured rock – I shuffle on with my arms outstretched, sneaking the occasional glance at the gaping crevices below, before arriving at my chosen stone. I perch, gazing awestruck at Mount Lefroy, Mount Victoria, the Victoria Glacier, and there, in the distance, is the tiny fragment of blue that had looked so vast just a fewhours ago: Lake Louise.

I’m momentarily rendered speechless, as any urbanite thrown into such an ethereal, ragged landscape is bound to be

I’m momentarily rendered speechless, as any urbanite thrown into such an ethereal, ragged landscape is bound to be, but the silence is punctured by a low growl and scattering rocks. Hell yes, I think, fumbling for the bell – here is my bear and I’m ready for it. Unfortunately, disappointment soon follows: it’s an epic false alarm. In the distance I see snow cascading in a grumbling, theatrical avalanche – they happen all the time here, apparently – while beside me a dusty goat kicks some stones and throws me a look that’s something between pity and distaste. I’m spent.

The next day I steer clear of the main route and take to the golden-hued back roads of Banff National Park in my car. If I thought Lake Louise was a dazzler, that was just the start of it. There’s Moraine Lake, set in the valley of Ten Peaks, where the light refracts off white rock flour deposited on the lake bed, creating a vast, vivid-turquoise pool. And I even stop to take pictures of the roads; uninterrupted, empty stretches of tarmac sitting beneath dazzling blue sky, tufty clouds and orange-tinged trees.

I pull up at Morant’s Curve, a spot made famous by Nicholas Morant, a photographer for the Canadian Pacific Railway who papped this exact meander of the Bow River and train track in the mid-20th century. It’s achingly beautiful, but rivalled by the view of the longest lake in the Canadian Rockies: Lake Minnewanka (sadly it’s pronounced mini-wonka), a 28km-long, glacial-fed lake that you can cruise by boat, or skim the shores of on your drive towards Banff town.

Unlike Lake Louise, Banff really is a town, with pubs, shops, and mean, mean traffic wardens (yep, you heard that right). At 1,400m, it’s also the highest town in Canada (unless you count Lake Louise, which obviously I don’t) and has plenty to keep me busy. I mountain-bike through the surrounding forest, soak in the healing waters of the thermal springs and take a cable car to the summit of Sulphur Mountain. It’s “brilliant for bear spotting,” several locals tell me, though everyone must be deluded or fibbing, because not a single bear indulges me.

I even stop to take pictures of the roads; uninterrupted, empty stretches of tarmac sitting beneath dazzling blue sky

Then there’s canoeing; a serene glide along the traffic-free Bow, and a largely hazard-free adventure (providing you avoid the low-hanging branches near the banks).

For some ramped-up exertion after my sedate paddle I start walking up to the distant summit of Tunnel Mountain, one of the more manageable peaks in the area – or so I’m told. Heaving my way up the track in the early evening sunshine, fitness types hurtle past me on their post-work run. Jogging. Up a mountain. Arriving at the top I pause for a rest and yet more vistas, this time over Banff and the Bow, which lazily snakes its way through the valley of mountains. My eyes are utterly spoilt.

But this mountain – and view – is just the warm up. The next morning’s an early start, and I’m pumped. Arriving at the foot of Mount Norquay, I take in today’s task: 2,225m of near-vertical grey rock.

My chaperone for the climb is the svelte Kevin, a thirty-something ex-professional skier who’s now an off-piste ski guide in the winter, a climbing teacher in the summer and a generally excellent-at-being-outdoors, very nice person all year round. The Via Ferrata – a climbing method that consists of metal rungs and cables being drilled into rocks – is the first new activity to be introduced into the park in three decades. “A lot of people are very protective of the area’s natural beauty,” Kevin explains.

Who can blame them? Today the conditions are perfect for my first attempt at scaling a proper mountain – a light wind ruffles my raspberry pink wind-proof shell (borrowed, I might add), the sun’s beating down ,and the rest of my kit – that’s harness, helmet and Clif Bars – is feeling good.

First, though, a demo. “Safety,” Kevin says, stopping in his tracks, “is key. You have two carabiners [he points to them – they’re the grey clippy metal things that will keep me safe] and both are attached to the wire. When you move one up to the next stretch of the safety cable,” he tugs at a wire embedded into the rock, “you leave your other one attached.” He pauses, grinning. “That way you never fall to your death.”

Spiky mountains, their tops veiled in snow, bask in dazzling sunshine, while the Bow river continues to glisten several thousand feet below

It’s simple, in theory. Kevin’s too cool to be dramatic, and really he’s just being honest. Via Ferrata – meaning the ‘iron way’ – is actually the ideal climbing introduction for a Londoner who can barely manage a monkey bar, let alone a mountain. “It’s just a ladder,” Kevin says, frowning, as I show him my tensed biceps. “A very long, high ladder.”

It’s also a ladder that reaches the clouds. My first step is trembly, and I’m giggly with the unfamiliarity of it all. But within a few rungs I’ve totally got the hang of it, and I’m using my legs and arms to haul myself up sheer, brutally rough exposed rock, in a speedy advance towards the summit.

But there’s no rush here in the Rockies. Around half-way up I double-check I’m attached to the wire, wedge my foot onto a rung and turn around, leaning back against the rock (I’ve spotted Kevin doing it) to appreciate the view sprawling below me. Spiky mountains, their tops veiled in snow, bask in dazzling sunshine, while the Bow river continues to glisten several thousand feet below and the glorious, uncluttered landscape of Banff National Park begs me to inhale some pollution-free air.

It’s a welcome pit-stop before the next stage, and Kevin pauses to prep me for this advanced ‘mountaineer route’. “It’s a little harder,” he warns, before we climb sideways across a cliff face to a huge chasm. Linking the two parts of the mountain and wiggling in the breeze is a single cable for my feet and two thinner wires at shoulder-height for my carabiners. No ladder, no bridge, just a 50m gap and a 2km drop. “How’s your tightrope walking?” he asks.

No ladder, no bridge, just a 50m gap and a 2km drop. “How’s your tightrope walking?” he asks.

It’s not too shabby, as it turns out. I put my faith in the carabiners and, looping them on to the cable, I start shuffling across, one foot in front of the other. As I do it, I just can’t help taking the occasional glance down at the rock below.

Reaching the safety of the other side, the eastern summit of Mount Norquay beckons, and we push on for the final ascent. Here, the rungs are surrounded by snow – even in summer you’ll find some at this altitude – and another guide’s gone ahead to de-ice the route for us. My hands throb, my energy levels feel suddenly depleted, and I’m desperate for a cuppa.

And where better to enjoy it? Surrounded by late-summer snowflakes, I take a seat in my rocky throne and gulp at the invigorating, hypnotic panorama of the Canadian Rockies. It’s just the type of adventure I’ve been craving; the exact view I’ve needed. Kevin claps me on the back: “You’ve climbed a fricking mountain,” he says. And it feels pretty good, too.

Travel information

Air Canada flies to Calgary from £640 return, aircanda.com; For more information on Banff National Park, Alberta and the Canadian Rockies visit banfflakelouise.com, travelalberta.co.uk and explore-canada.co.uk; Book caving and climbing via canmorecavetours.com and summer.banffnorquay.com