It is the beginning of summer and all around me I can see bright, white snow. I am not cold, but instead surprisingly warm: the sun is shining and there is no wind.

I'm standing on the Jungfraujoch in Switzerland, the highest point you can reach by train in Europe. It is utterly beautiful, with an expanse of white valley laid out in front of me.

The Jungfraujoch - where you can see both the Jungfrau and Mönch mountains - is a busy tourist destination but that's understandable. It feels pretty special to survey the sights from 3,454m (over 11,000 ft) above sea level.

My journey up took two trains, from Interlaken and then Lauterbrunnen, climbing higher and higher into the mountains on the Jungfraubahn, going through the Eiger on the way. The train stops twice as you ascend from Kleine Scheidegg to the Jungfraujoch, to avoid risking altitude sickness and also for some tasters of the marvellous views to come.

The weather can play havoc with the views but we were in luck. At one point, while eating lunch in the restaurant, cloud cover made it impossible to see anything but it was also so bright that sunglasses were a necessity. Be warned, however, that it can get extremely cold here, especially when the wind is blowing. The average temperature across the year is -7.9C.

The Jungfrau is hugely popular and buzzes with tourists from all round the world. It does not only offer great views - wander out onto the Sphinx terrace for the best - but also a choice of restaurants (not least a Bollywood one), a number of shops including a rather chaotic Lindt discount store, the "Alpine sensation" which gives a quick history of the mountain and the construction of the railway, and an ice palace, with some very impressive sculptures all gleaming with a slight blueish hue. There is also a sledge park and the possibility of skiing, snowboarding and zip lining on the Aletsch Glacier.

But my trip to the top of the Jungfrau was only one of a number of rail trips taken as part of Great Rail Journeys' Jungfrau Express tour. As someone who loves mountains and lakes, I adored the scenery, whether I was travelling from Meiringen (our base), Interlaken, or on a rather special steam cog train which climbed up the Rothorn mountain.

And our base couldn't have been much more convenient. The 4 star art deco Parkhotel du Sauvage, in Meiringen is just five minutes from the train station, near a cable car which takes you up into the mountains to the Alpen Tower, and minutes from St Michael's Church with its fascinating archaeological excavations, going back to the 11th century. It is also next door to the charming Sherlock Holmes museum and just 15 minutes walk from the funicular which takes you to the spectacular Reichenbach Falls, famous for the fight between Sherlock Holmes and his nemesis, James Moriarty,

Sir Arthur Conan Doyle even used to stay at the Hotel du Sauvage, and the museum is a tribute to him, while a visit to the Falls is a must. We reached them by the funicular (although you can walk) and it was one of the highlights of our trip.

Travelling up the Rothorn railway by steam train, just as people did when it first opened in 1892, was another. The setting is beautiful and you can even ride on the footplate (if you book in advance) as you climb into the heart of the Bernese Alps. Train aficionados should note that Mike Ellis from the Brienz Rothorn Bahn actually offers tours of the workshop too.

The train itself starts from the pretty town of Brienz, on the edge of Lake Lucerne. From here we took a boat to Interlaken, which was bigger than I expected with lots of shops to explore (including some delicious looking chocolate shops) and restaurants to sample. Be warned, however, that Switzerland is very expensive, so I didn't buy very much (pity my children).

Funnily enough, the best view of the city is from one of the ugliest buildings, the Metropole Hotel, which has a panoramic restaurant - a lovely place to sit with a drink and cake.

There are also an endless array of paragliders, who float down in the middle of the city. I know my son would have loved to have tried this and got the sense that Interlaken would be a perfect base for an outdoors mountain holiday.

The city is also blessed with its own funicular, which takes visitors up to the Harder Kulm mountain. With crowds of people wanting to take in views of the Eiger, Mönch and Jungfrau mountains, as well as the gorgeous lakes Thun and Brienz, it was by far the busiest form of transport we tried.

However, it was unquestionably worth the squash as the views were absolutely wonderful, particularly from the glass viewing platform which is at 1,322m above sea level - although those who are scared of heights might disagree .

All in all, the trip was a real treat. The trains - unlike many of their British equivalents - were always on time and a wonderful way to discover the magnificent scenery, and I felt as if it was all a real breath of fresh air.