The layout of a big station tells you how much time you need

Two basic layouts and everything that follows from them

A terminus is a station where the tracks stop. Trains come in, everybody walks toward the buffers, and the concourse sits across the end of the platforms so that all passengers funnel through the same space. A through station has tracks running past it, platforms alongside them, and access from a bridge or a subway.

The difference is not architectural trivia; it decides how you move. In a terminus every platform is reachable on the flat from a single point, which is why they are generally easier with luggage and with limited mobility, and why the walk from the front of a long train can be considerable.

In a through station you almost always change level to change platform, and the distance between platform ends can be substantial in the other direction. Neither is better overall. They are good at different things, and the one you are in determines how much time a connection really needs.

Why the great terminals were built where they were

Nineteenth-century railway companies approached cities from different directions and stopped at the edge of the built-up area, because buying and demolishing property in the centre was ruinously expensive. That is why so many large cities have several major stations, each serving one part of the country, rather than one central station serving everything.

The consequence for a traveller crossing such a city is a cross-town transfer between terminals, using a metro, a bus or a walk, and that transfer is a separate journey with its own risks. It is also why through-running tunnels have been built under so many cities in recent decades: they retrofit a connection the original companies never had reason to build.

The grandeur of these buildings had a commercial purpose too. A terminus was the shop window of a private railway company competing for traffic, and the ornament was advertising. That is worth knowing while you are looking up at a roof that has no engineering need to be beautiful.

Platform allocation is a live problem, not a fixed fact

On many long-distance networks the platform for a departing train is confirmed only a short time before it leaves, because the station is juggling arrivals, cleaning, crew changes and delays in real time. This is why crowds stand facing the departure board rather than sitting down, and why the announcement produces a sudden mass movement.

Some networks do the opposite and allocate platforms months in advance, printing them in timetables and on tickets. Both approaches are defensible: fixed allocation lets passengers plan and spreads crowds, while late allocation gives the operator flexibility to recover from disruption.

The practical habit that covers both is to know which end of the train you want before the platform is announced. Reservations, coach letters and carriage diagrams on the platform tell you where to stand, and standing in the right place turns a scramble into a walk.

Where the time actually goes inside a station

The published minimum connection time for a station is a real figure calculated by the operator, and it accounts for the walking distances involved, but it assumes an able passenger who knows the building and does not stop. Anyone with luggage, a pushchair, a ticket to collect or an unfamiliar layout should treat it as a floor rather than an estimate.

Vertical movement is the main consumer of time and the main source of failure. Lifts in older stations are few and often at one end, escalators are frequently out of service, and a subway under six platforms can involve more distance than the map suggests.

Security and border controls, where they exist, change the arithmetic entirely. Some international services require check-in well before departure, which makes the connection a matter of a published deadline rather than a walking time.

The facilities that matter and where they hide

Left luggage is the single most useful thing in a large station and the least consistently provided. Where it exists it may be lockers, a staffed counter with its own opening hours, or an independent shop nearby, and in some countries it has been withdrawn entirely for security reasons. A city with no station left luggage changes how a day between trains can be spent.

Ticket offices are contracting almost everywhere, which matters more than it sounds. Machines handle standard journeys well and handle unusual ones badly, and complicated international or multi-operator tickets are exactly the case where a human being is still faster and more reliable.

Lounges, waiting rooms and quiet corners follow a hierarchy that is worth knowing: some are ticketed, some are for particular classes, and many stations retain an ordinary waiting room that nobody advertises. On a long wait in a cold station, finding it is the difference between an unpleasant hour and a fine one.