By the time you disembark, you will have covered one fifth of the Earth’s circumference by train. The Moscow to Vladivostok route covers 9,900 km of largely untouched Russian landscape, making it one of the longest train journeys in the world. Highlights include the pine-covered Urals and the 180 km section alongside the clear waters of the beautiful Lake Baikal.

An alternative is the Trans-Mongolian Railway, which peels off from the Vladivostok route and crosses the undulating Mongolian steppe to Ulaanbaatur and eventually Beijing. Look out for the shaggy Mongol horses on the steppe; believed to be unchanged since the time of Genghis Khan, they outnumber the country’s human population.

Journey time 7 days, from £160. More information here.