Five major train stations aren't hard because of the trains — they're hard because of the building: multiple operators sharing one name, platforms that aren't posted until minutes before departure, track numbers that only make sense once you know what they encode, and two stations close enough to share a reputation but not a platform. This isn't which operator to book — that's the European Train Guide — or which card to tap — that's City Transit Cards. It's the five minutes of not knowing where you are that actually costs people their train.
Worth knowing
Platforms aren't posted until roughly 15–20 minutes before departure, so the whole departure hall reads the board at the same moment and moves as one crowd. Once your train shows a platform, that's the signal to go — not before.
Eurostar runs from its own international terminal inside the station, separate from the domestic Grandes Lignes hall — its own security screening and passport control, and its own departure lounge. Arriving from the Métro or RER, you still have to find that entrance before you reach any check-in queue.
The EU Entry/Exit System has operated since October 2025 and can add biometric registration for eligible non-EU short-stay travellers. For London-bound Standard and Plus tickets, Eurostar currently recommends arriving 75–90 minutes before departure even though the ticket gates close 30 minutes before; use the time printed on your ticket because guidance can change.
Worth knowing
JR East, Odakyu, Keio, Tokyo Metro and Toei each run their own ticket gates inside "Shinjuku Station." Switching between them usually means exiting through one company's gates and re-entering through another's — not just walking to a different platform.
With 200-plus exits, note the exit number printed on the signs near your ticket gate before you go underground. Retracing your steps without it is genuinely how people lose the better part of an hour here — the East, West, South and New South exits alone surface blocks apart.
Because each operator's paid zone is separate, an IC card top-up machine inside one company's gates doesn't help once you've crossed to another's — build a few extra minutes into any transfer. For how the card itself works, see City Transit Cards.
Worth knowing
The Metro (Linea A/B) entrance isn't visible from the main departure hall — it's down a separate staircase off the underground concourse. Looking up at the departure boards won't point you to it.
The upper "Galleria" level — shops and food — sits a full floor above the platforms themselves, so track access is always one level down from where the station first appears to end.
Staff from Trenitalia or RFI wear branded uniforms; unsolicited help with bags at platform level is worth waving off without engaging. For the fuller pattern of what to watch for around the station, see Common Scams; for where to actually leave a bag and what it costs, see Luggage Storage.
Worth knowing
The track (Gleis) number tells you the level before you even look for a map — 1 to 8 are underground, 11 to 16 are up top. Read the track number on the board first; it stops a wrong-level dash to the escalators.
The glass "cathedral" design lets you see clear across the whole building, which is deceptive — the two rail lines cross at right angles on different levels, so a platform that looks close by sight can still be two escalators and a level change away.
Each platform is also split into lettered sectors (A through G) matching where a specific carriage stops — check the Wagenstandsanzeiger board for your sector, not just the platform number, especially with a reserved seat.
Worth knowing
King's Cross and St Pancras are two different stations run by different operators, not two entrances to one building — and Eurostar departs only from St Pancras International. Turning up at the wrong one is a genuine, repeated mistake, not a rare one.
The two share an Underground station wedged between them, which is exactly why people conflate the mainline stations sitting above it. The walk between the two street-level entrances runs about 3–4 minutes, via Pancras Square or the shared Underground passage.
Arriving on a domestic train into King's Cross to catch a Eurostar from St Pancras is not "already at the station" — budget the walk and the wayfinding as their own step, separate from the connection time between trains. For who runs the domestic side, see the European Train Guide.