Flickering past the train window are birch trees and patches of spring snow.
This ever-changing yet never changing scenery has become the surprising highlight of my time on the Trans Siberian Express. It's slow travel at its best, where the chief thrill is the journey itself: the cosy carriages, on board camaraderie, and the constant edging forward across the vastness of Russia.
The whole trip from Moscow to Beijing is a journey of 4736 miles, which takes six days on an ordinary through train, or 16 days on the Tsar's Gold tourist train, which makes sightseeing stops along the way.
This German-run "cruising on wheels" experience is for people who prefer everything pre-booked and arranged in advance and don't fancy tackling the language barrier on regular Russian trains.
I board the Tsar's Gold train in Yekaterinburg, just east of the Ural Mountains, for a three-night ride to Irkutsk, not really knowing what to expect.
We chug out of the city and, passing the tiny kitchen at the end of the carriage, I enter the toasty dining car and begin getting to know the jolly group of about 20 English speakers. Most passengers on the train are German, but the English-speaking group includes Britons, Danes, Dutch, Italians, Americans and a Spaniard. We stick together for meals and tours.
It is nice to warm through, eat a hearty meal of fish salad, cabbage soup, and "beef in Russian Monastic Manner", and move on from the gloomy spots I'd visited before boarding in Yekaterinburg. It was there that Tsar Nicholas II and his family were shot and killed in 1918 before their bodies were mutilated and dumped down a well there.
I learn it wasn't just the Imperial family whose enforced journey eastwards was doomed, when after dinner, Larissa, our English-speaking guide, gives her evening talk on Siberia.
"It's been a place of exile for 300 years, with perhaps 21 million inmates passing through the gulags in total," she says. The majority were sent east during Stalin's time, when he expanded the prison camps.
"On the trains, there were gun emplacements on top of the carriages and hooks underneath to kill anyone trying to escape."
I wouldn't fancy anyone's chances in this wilderness. Between the cities there is barely a sign of life, save for a meagre hut or two close by the train tracks every few hours.
I'd imagined the size of towns would shrink as the train trundled further into Siberia, but Novosibirsk, the first stop after Yekaterinburg and 2000 miles east of Moscow, is big and bombastic. Soviet-era buildings here include the country's largest opera house and a prominent Lenin statue flanked by five heroic workers.
At Krasnoyarsk, while other passengers are having a city tour, I ask train manager Hans for a peek in all the carriages. Squeezing past a large man with a small vacuum cleaner, I enter the Classic category of cabin - a basic compartment with two bench seats that convert to four bunks, with shared toilets at either end of the carriage. It costs about £4000 one-way per person.
"All our classes include the same meals and sightseeing," says Hans, as we move down the corridor. The windows of the Nostalgia cabin, with one shower shared between two cabins, are being cleaned inside and out "so our guests can always take good photographs", he explains. At the front of the train are swish modern Bolshoi Class compartments with double beds and an en suite toilet and shower.
I catch up with the group walking towards the city with local guide Irena.
Down by the river promenade, the spring sun lifts everyone's spirits. Sitting on the open deck of a large pleasure boat I fall into a beer-fuelled chat with some young Russian lads about football and pop music.
On my last night aboard the train I return to my compartment tipsy from a robust vodka tasting evening with Larissa and the group. I fall asleep wondering if she really said Tsar Peter the Great made dancing and moustaches compulsory.
We joke as the train approaches Irkutsk the following day ("Yes - Peter the Great really did that," Larissa says). Then after my 100-hour stint on the train, I pop back to the compartment for a last stare into the birch forests.
The monotony becomes magical, the carriages homely, and several of the group are now friends. What a cracking experience, and what a wrench to leave for my six-hour flight back to Moscow.
The Russia Experience (trans-siberian.co.uk, 0845 521 2910) has a 16-day Tsar's Gold train journey from Moscow to Beijing (or vice versa) starting at £3580 per person, in Standard category based on two people travelling, rising to £11,995 per person (based on two) in Bolshoi Class, with all meals, sightseeing and transfers but excluding flights. The Golden Eagle - from Moscow to Vladivostock - starts at £9695 per person.