Crossing a continent by train

There is a threshold, somewhere around four hours of journey time, where the train stops being the slow option. Below it, rail wins on almost every measure that matters: no airport transfer, no security theatre, no baggage carousel, a seat you can leave, a window worth looking out of, and a station in the middle of the city at both ends.

Above that threshold the calculation changes - but not as much as people assume, because the sleeper train removes the journey from your waking life entirely.

The four-hour rule, and why it is really a six-hour rule

City centre to city centre, a four-hour train ride is usually faster than the equivalent flight once you count getting to the airport two hours early, the flight itself, and getting from a peripheral airport into town. Paris–London, Madrid–Barcelona, Tokyo–Osaka and Milan–Rome are all comfortably in train territory, which is why the airlines largely stopped competing on them.

In practice the threshold sits closer to six hours if you value the time. On a train you can work, eat a real meal, sleep, walk about and use your phone the whole way. Four hours of usable time beats ninety minutes of unusable time plus three hours of queueing.

How sleeper trains actually work

Sleepers are the part people get wrong, usually by booking the cheapest option and then being surprised. The tiers are broadly consistent across countries:

• Seats. Cheapest, and fine for one night if you are young or desperate. You will not sleep well.
• Couchettes. Four or six bunks in a shared compartment, bedding provided, mixed or single-sex depending on the operator. Sociable, cheap, and a lottery on snoring.
• Sleepers. One to three berths, a washbasin in the compartment, a door that locks properly. This is the tier worth paying for.
• Private sleepers with a shower. Expensive, occasionally cheaper than a hotel plus a flight when you compare honestly.

Two things nobody mentions. First, sleeper berths sell out far earlier than seats, often months ahead in summer, and prices rise steeply as they go. Second, the train is at its best in the hour after you wake up, when tea arrives whether you asked for it or not and the landscape outside has completely changed.

Booking: the one rule that saves the most money

Advance fares on long-distance rail behave like airline fares - released at a fixed point, cheapest at the start, rising as seats sell. In much of Europe that release is 3 to 6 months out. In Japan the reservation window opens one month before departure, on the dot.

The rule: find out when booking opens for your specific route and book on that day. The difference between an advance fare and a walk-up fare on a long route can be a factor of four. Flexible passes are a different product with a different logic - worth it if you are making many long hops in a short window, rarely worth it for three or four journeys.

Routes worth taking for their own sake

The Trans-Siberian is the obvious one: 9,289 kilometres from Moscow to Vladivostok, roughly seven days without stops, crossing seven time zones and 87 cities. For most of its history the entire timetable was printed in Moscow time regardless of where you actually were.

The Bernina and Glacier lines in Switzerland do in a few hours what most railways do in a week, climbing through spiral tunnels and over viaducts that are themselves World Heritage listed.

Sri Lanka's hill country line to Ella runs four hours through tea plantations with the doors open, and somebody's grandmother will tell you to move back from the doorway in a language you do not speak and you will understand every word.

Indian Railways is not a scenic route, it is a country. Twenty million passengers a day, 68,000 kilometres of track, and the single best place to be introduced to eleven people you did not ask to meet.

Canada's transcontinental gives priority to freight, which means the passenger service can run many hours late and the dining car simply keeps serving, like a hotel that happens to have wheels.

Practicalities that make a long journey pleasant

• Book a seat facing forwards and away from the sun for the longest leg. On a twelve-hour day this matters more than legroom.
• Bring more food than you need, and something to share. Sharing food is the fastest social currency on any train in the world.
• A power bank, because sockets on older rolling stock are theoretical.
• Earplugs and an eye mask even in a private sleeper. Trains change crew at three in the morning and it is not quiet.
• A refillable bottle. Most long-distance trains have hot water; some have nothing at all.
• Download offline maps. Knowing which unannounced station you are at is worth more than you would think.

The argument that has nothing to do with time

The real case for rail is not efficiency. It is that a train gives you the distance back. Flying deletes the space between two places - you go up in one country and down in another with nothing in between. A train makes you cross it: the suburbs thinning out, the crops changing, the roof tiles changing colour, the language on the platform announcements shifting somewhere around lunchtime.

That is the part you remember, and it is the reason a fourteen-hour train is not fourteen hours wasted. It is the trip, rather than the gap before it starts.