If you want the measure of just how pleasant the Norwegians are, I advise a visit to the Laerdal tunnel. The tunnel is part of the route between Oslo and Bergen; at just over 24km (15 miles) long, it is the longest road tunnel in the world. For safety’s sake, every 6km there is a chance to turn around; and every huge lay-by is designed to look like a cave carved into a glacier, complete with glowing, dawny lights. Our guide, Leila, took us in her car to the first of these.

“When the tunnel was opened in 2000,” she said, “young people would stop in this lay-by and stay overnight, have parties.” I couldn’t blame them – it was pretty amazing. “But it wasn’t really safe.” Quite right, I thought, but, knowing the yobbish nightlife of Britain, wondered how it would be possible to get the kids out. Leila pointed to a sign, the international symbol for No Stopping. “So that was put up,” she said, “and the problem was over.”

See? I love Norway. I’ve loved it since I read about the great explorers of this young country, men like Roald Amundsen, discoverer of the Northwest Passage and first man at the South Pole. I loved it for its eerie folk tales and their trickster hero Askeladden, the Ashlad. But I had been only once – to see Amundsen’s sturdy ship, the Fram, now in an Oslo museum – and I wanted to come back with my family, to see more of this enticing place.

We were halfway through our trip when we visited the party-free tunnel. We – me, my husband Francis and our six-year-old, Theo – had begun in Oslo. What six-year-old could argue with the simple, yet awesome, spectacle of Oslo’s Viking Ships Museum?

The museum – along with most of the city’s other museums – is a short bus ride out of the city, on the Bygdøy peninsula (in summer you can take a ferry). Visit and you understand the awe a Viking force would have engendered. The two largest ships, discovered in burial mounds in the early 1900s, are each more than 20m (65ft) long and well over a thousand years old, yet each looks ready, still, to ride the whale-road of the ocean. Theo had read about the Vikings; these ships, and their treasure troves, made what he had read real.

Now a short pause for a word of warning. Of course, after our visit to the museum we were as hungry as Nordic raiders. We had discovered the Norwegian chain Deli de Luca, a bit like Pret A Manger, but with a little more on offer. There is, however, one crucial difference. If Theo and I had had a box of sushi each and a coffee in Pret, let’s say, we’d have paid £14. The same in Deli de Luca was over twice that.

Norway is many things, but inexpensive is not one of them. Both Oslo and Bergen have plenty of trendy restaurants, but we enjoyed the traditional meals we ate at the Gamle Rådhus in Oslo (reindeer with lingonberry sauce; delicious) and To Kokker in Bergen (cloudberries and cream; sublime). Still, we reeled when the bills came.

We left Oslo for the north. We were headed for Bergen, but we’d take the train first to Flåm, a sweet little town nestling in a fjord, and then travel by boat along the Sognefjord to Gudvagen and Voss. It takes about four spectacular hours to travel by train from Oslo to Myrdal, up through Norway’s high, bleak central plateau. Here is where Amundsen trained for his polar journey; here the houses are few and far between, though with their bright red paint and pair of reindeer antlers over the doors, they look cosy against the black rock and the white snow (some have grass roofs; a goat can be handy for keeping this in trim, I’m told).

At Myrdal you join the Flåmsbana scenic railway, still one of the world’s engineering wonders, dropping almost 900m over its 20km length; The Flåm railway is one of the world’s steepest railway lines on normal gauge.

A ride on the Flåmsbana is part of the Tourist Board’s “Norway in a Nutshell” tour, as is the breathtaking two-hour ferry trip we took along the fjord to Gudvagen. I would count this as among the finest couple of hours of my life, not least because the sweet waitress in the little shipboard café handed Theo hot pancakes without a kroner changing hands and replaced his hot chocolate when he dropped it. If you wonder why the Norwegians tell stories filled with savage trolls, you have only to look at the peaks that loom over the cold, bright water of the fjords. Here is wild and forbidding beauty.

Bergen is another couple of hours’ train ride from Voss – a charming town with a lot of sport, skiing and boating, in winter and summer – and I think it’s here, within this city’s seven hills, that I would make my Norwegian home.

Of course, Bergen has its disadvantages. People there tell a story about a traveller who asks a local boy how long it’s been raining. “I don’t know,” says the boy. “I’m only 13.”

Bergen is made especially lovely by the survival of Bryggen, the wooden shops and houses by the harbour that are an 18th-century legacy of the city’s Hanseatic past. It is a lovely city to explore on foot, or take the Fløibanen funicular railway for a quick trip above the city and see it spread out below. Theo loved Bergen’s aquarium, reached by a tiny ferry that leaves every ten minutes or so to cross the harbour; and he loved our hotel, as did we – the new Clarion Collection Hotel Havnekontoret.

Norway in a Nutshell is a whirlwind tour. But when you love a place, you want to go back; and that’s what we talk about now. Of course, it’s not the place to go if you want to party in a tunnel, but that’s OK with me.

Need to know

Getting there: Erica Wagner and family flew with Norwegian Air Shuttle (00 47 21 49 00 15, www.norwegian.no) from Stansted to Oslo and back from Bergen. Fares start at £34 each way.

Getting around: Flytoget (www.flytoget.no) airport express train takes 19 minutes to Oslo Central Station. Train and bus travel around Norway can be booked through NSB (www.nsb.no). Fjord Tours (www.fjord-tours.com) offers one to three-day Norway in a Nutshell tours using public transport.

Staying: SAS Radisson Plaza Hotel, Oslo (00 47 22 05 80 00, www.radissonsas.com) has B&B doubles from £101; Fretheim Hotel, Flam (57 63 63 00, www.fretheim-hotel.no), from £88; Fleischer’s Hotel, Voss (56 52 05 00, www.fleischers.no), from £104; Clarion Collection Hotel Havnekontoret, Bergen (55 60 11 00, www.choicehotels.no), from £85.

Reading: The Insight Compact Guide Norway (£5.99) is published this month.

Further information: www.visitoslo.com; www.visitbergen.com; www.visitnorway.com/uk.

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