Her mother quits partway through, but Dana Filek-Gibson bikes on to keep up with her sadistically inexhaustible father in the perilous cliffs of Vietnam’s northwest.

In every town, in every province, we leave the locals both confused and impressed.

Khoe!” they exclaim, pointing to my parents and their mud-splattered bicycles. The men, cigarettes dangling from their mouths, squeeze our tyres and click our gears. Children stare at us through their mothers’ legs, bewildered. Ever since we left Hanoi, the three of us have become increasingly popular: me, a Vietnamese-speaking foreigner, and my parents, a couple of old folks on two wheels.

Out here, where people live on sloping mountainsides or perilously close to cliffs, it’s not every day you see another human being — let alone a westerner — roll by on a push-bike. You’re more likely to find boys leading buffaloes into the fields or women carrying baskets, thick leather straps across their foreheads, as they wander out of the dense forest.

On Highway 6 heading west to the Lao border, bicycles rarely make an appearance. The Northwest Loop, a circuit running out of Hanoi toward Dien Bien Phu and then north to Sapa, is a world apart from the chaos of urban Vietnam. Full of winding mountain roads and wide river valleys, this region holds some of the most breathtaking and challenging terrain the country has to offer.

For my father, it is exactly what heaven looks like. An Ironman triathlete and general fitness addict, he practically squeals with joy as we ascend Pha Din Pass, a never-ending, shadeless uphill that takes us 1,600 metres above sea level. When we run out of water halfway up the 16-kilometre climb, my father can barely conceal a smile as he beams, “Well, there’s no turning back now!”

My mother, on the other hand, isn’t exactly thrilled. The cycling would be manageable, she insists, if it weren’t for all the hills. Guardrails are nonexistent, unless you count the occasional concrete post sticking out of the grass, inches away from the edge. An equally vertical rock face on the opposite side of the road is forever under construction, men with jackhammers raining down chunks of stone upon us.

After years of living in jam-packed cities, I find the northwest Vietnam’s larger-than-life landscapes almost otherworldly. You’ll be hard-pressed to locate amenities like English speakers or functional showers, but that is part of the appeal.

As we move out of Hanoi toward Mai Chau, a small community shielded by limestone karsts, local ethnic Thai women begin to appear in greater numbers, their hair piled high atop their heads. Old men in berets smoke massive wooden thuoc Lao pipes. We whiz downhill around tight curves and back to sea level, breathless as we take on the next dramatic climb towards Tuan Giao.

On our final day before Sapa, we stop in Tam Duong. Even from a distance, Tram Ton Pass appears to be a wall of earth, looming large above the tiny village. My mother takes one look at tomorrow’s route and refuses. We put her on a bus in the morning and I head out with my father.

It’s a 25-kilometre ride up to the highest point. With every switchback a new waterfall appears, charging under the asphalt, which is somehow attached to this mountain and yet still able to make space for running water. The odd truck passes, groaning and screeching its way skyward, dangerously close to both me and the edge of a cliff. None of it seems real — the mountains, the rivers, the dark snake of a road winding forward and up — but for the shadow of my father in the distance. After 11 straight days of riding, my quads are killing me. I’ve become comfortable with the dirt and the snail’s pace at which I’m crawling up this hill. But being alone in these hills, trying to find the sky beyond every turn, makes me feel I’ve left Vietnam completely.

I catch up with my father just as he’s leaning his bike against a post. A group of men sit inside the tarpaulin cave someone has erected at the edge of the road. They’ve been staring ever since a sweaty, dirty six-foot-two foreign man rolled into their line of sight. Only now, as we turn and acknowledge them, a plastic jug of rice wine is extracted from between them to the tune of several hellos and a lot of laughter.

“It’s freezing,” I say. Stuck in the middle of a cloud, the temperature has been steadily dropping since the sun abandoned us a few kilometres below. My legs cramp as we sit, protesting the ride, and even my father winces a little as he lowers himself onto a miniature stool beside the fire. Shots are poured, and after a couple rounds of no-I-couldn’t we agree to one apiece.

Without the word for “summit”, it takes us a few tries, but eventually everyone understands that I want to know where the top of this god-forsaken hill is. A moment of silence passes between us, and then the men break into laughter as the lone woman replies, smiling: “You’re already here.”

Once I translate for my father, he is happy, too. I pump my fists and shout for joy, the only person in the tent excited by the news. Someone offers me barbecued meat, and even though I see the crisp, curled foot of what might be a pigeon attached to the morsel, I pretend not to notice and devour the snack. My father suggests we keep going so my mother isn’t left alone for an entire day. In minutes we are gone, thanking everyone, cresting the top of the 2,000-metre pass, and sliding our way out of the cloud and back to Vietnam.