Norwegian trains have their nuisance factors neatly divided. There's a carriage for those with small children, one where you're not allowed pets, and one for smokers in which the dogs are allowed.

We were directed to our seats by a friendly passenger with a failed Viking mustache, and installed ourselves near a man smoking a long curly pipe filled with foul tobacco; its thin stem wound down through a tuft of fuzzy hair beneath his lower lip.Trees grow in the most impossible places in this vertically rocky country, and the same seems to be true of what the men wear on their faces; maybe it's something to do with the climate.

Recovering slowly from our dawn start, we wound out of Oslo in brilliant sunshine. Apparently, it used to be a rather gray and gloomy city, and in the rain it's dreary enough; but the large public buildings are now painted in tasteful colors, and the suburban houses among their trees are russet, yellow, blue - and surprisingly much closer together than you would expect for a country that has only 4 million people in its vast landscape.

I had never been to Norway before, but my husband, Gavin Lyall, had set part of his thriller "Blame the Dead" there. I recalled his character had consulted a guidebook: "I read of their mountains, prices, morals. All seemed high."

Having been there before, he didn't mind missing the scenery by reading a book, but reading wasn't easy: every time you got down to it in a tunnel, you flashed back into the light; every time you gave up to look out of a window, a tunnel or snowbreak would slap you into darkness again. It was tempting to close your eyes.

When I woke we were back in deep winter: stark branches against the snow, flat frozen lakes. At the highest point, skiers got off and hissed into the distance. Norwegians ski well into their 90s; it must be all that fish and meatballs.

Our red train swung through the bleak uplands, curling endlessly in the snow. The railway's response to this wintry landscape was to offer us ice cream. Looking out of the window at the weird white banks and gullies made us feel like we were traveling through a Cornetto ourselves.

While we were still high up, we reached Myrdal, where our "Norway in a Nutshell" party got off and boarded a small gravity-defying train, to wend down the mountain, through 20 tunnels, from stark winter - the ghost trees barely a whisper against the rock - going almost vertically past the first faint bloom of green on a field, to full spring, green trees and flowers in the valley floor.

We were allowed to stop and gape at one of the many waterfalls; but here, and in the fjord, the most impressive were not necessarily the biggest: a slight curtain of water blowing away in the wind on a thread that mists out and is gone can be spectacular.

Arriving at Flam, we had time to get some lunch. There was beer and wine on sale, but the prudent traveler in Norway carries a hip flask: apart from the astronomical cost, spirits can't be served before one o'clock or on Sundays and holidays or indeed at all in some places.

The boat trip we took up the Sognefjord was the best bit of our journey. You looked up at towering black walls of rock, and, as the boat moved, an even higher snow-topped mountain would appear unbelievably behind them. We passed handkerchief-size green fields and villages you can only reach by boat.

So finally to Voss, a pleasant enough town; and a hamburger in the station buffet, where we sat warmly watching a small seaplane land and take off on the lake; then a local train to Bergen, still light at 10 in the evening, in time to collapse into the excellent Neptune hotel and brace ourselves for Independence Day.

Norwegians celebrate independence on May 17 because that's when they first got together to declare a constitution and freedom, but it didn't last long: having been Danish for hundreds of years, they were part of Sweden for nearly another hundred after that.

But May 17 is still the great day. We were surprised by how easily we found a place to watch; the reason was that just about everybody in Bergen was in the parade: police, firemen, schoolchildren, a bunch of people in wheelchairs, nurses, doctors, post-office workers, each with a blaring band and flags waving. And their partners and children, some in pushchairs and plenty with balloons.