There's almost always a whiff of romance around boarding an overnight train, and the 9.30pm express from Hanoi to Lao Cai, on the Vietnam-China border, is no different.

Guards in prim nylon uniforms and shiny badges stand on the platform under fluorescent lamps that pierce the evening gloam as a gecko scampers across the side of a carriage, even greener than the paintwork. Whistles blow and a prodigious number of flags are waved as we scurry, like the gecko, into our four-berth compartment.

As the train begins to shunt slowly out of the station, hawkers quicken their step in time with the rolling wheels, tapping on the window with cans of Ha-Noi beer to attract one more sale: a drink or a glazed pastry obtained from one of the dozen French patisseries that line the station forecourt.

The compartment is small, efficient and clean, with a desk lamp and a table on which we slap down playing cards and beer bought from the window-tappers. Before long, though, we swing our legs up onto our bunks and are rocked to sleep in our cast-iron cradles.

Lao Cai is a busy, modern town defined by Chinese fluorescence and hasty architecture. We sit down to a breakfast of beef pho noodles and readjust after a night of clanking points and swaying toilets.

Every year, tens of thousands of tourists eat breakfast or dinner in Lao Cai, on their way to or from the remote hills of northern Vietnam.

Despite rising tourist numbers, the road to the old French hill station of Sapa feels wild, passing increasingly scenic panoramas of rice terraces, forests and villages.

As we pass through, dogs half-heartedly chase our car uphill and Hmong children wearing bright skirts and brighter smiles wave shyly.

A welcoming town of log fires, massage shops and restaurants, Sapa spreads across the hills above the rice terraces like an alpine retreat, but our destination lies in the mountains beyond - Fansipan, which, at 3,143 metres, is the highest peak in Indochina.

The climb begins in a car park about 16km outside town, with a talk by a park ranger in a woolly hat about the twin perils of litter and fire. And then we are off, navigating a jumble of boulders, fording streams and slipping on the red laterite earth.

It's a steep path and as the views of the mountain begin to unfold, it's difficult to decide whether the massive bulk is inspiring and magnificent or intimidating and crushingly distant.

Before we have made up our minds, a crowd of Vietnamese students in thin plimsolls jog past in high spirits, carrying a red national flag to plant on the summit, to prove they have stood at their country's highest point.

We stop for a lunch of eggs, rice, cucumber and lumps of bone and skin that masquerade as chicken, before more climbing, now sometimes on steel ladders bolted into the vertical rock. Our late afternoon arrival at "base camp" doesn't come soon enough.

Base camp is certainly basic; a small hut on a shelf of grass and rock below steep crags. There is no "lights out" for there are no lights, and the bed is simply a camouflaged Vietnam Army-issue sleeping bag on a wooden platform.

I drift off to sleep to the snoring of my companions and of strangers, to the wind in the trees and to a scrabbling noise under the platform beneath my head, which may or may not be a rat.

We wake at 3am. The rat is asleep but the wind is still rustling branches and has swept in a thick white mist that cloaks everything in a blanket of dampness, obscuring stars, trees, stones and companions.

Head torches bobbing, we are aware only of the steepness of the path and a shortness of breath as we pass the rarefied height of 3,000 metres.

Dawn breaks with no sign of the sun and we climb the last few hundred metres through an otherworldly grey shroud to the summit plateau.

However, such view as there is through the gloom is despoiled by the ongoing construction of a cable-car complex. Cables and pipes line the path like handrails and a legion of workers cut and polish stone as they put the finishing touches to the grand steps and a temple that sit atop the mountain.

The cable car is a wildly ambitious project that opened in February. It's listed as the longest three-rope cable car in the world, at just over 6km, with a vertical ascent of more than 1,500 metres. The project cost US$180 million and it reduces a two-day climb to a smooth, 20-minute ascent through the clouds. The project has rather destroyed the wild beauty of the peak, but, in truth, we are happy to escape the cold mist and sup hot Vietnamese coffee in the newly constructed restaurant. And by forking out US$30 each to ride down, we also save ourselves two days of slithering over greasy rocks.

As we're whisked down to Sapa, the mist sometimes swirls apart to reveal sweeping panoramas of rice terraces and villages.

Tens of thousands of people used the cable car in its first month of operation, but there is still satisfaction in standing on a summit that has been achieved through effort and toil.

What's more, the comforts of Sapa have been magnified for us "mountain men" on our return, and the view back to Fansipan, which once seemed so high and distant from the balcony of our hotel, now brings a hard-earned sense of fulfilment.