How we decide

What goes on the clock.

Same method on every route. Here is what we count, what we assume, and what we leave out.

The airport trip counts

Published flight times run gate to gate. If you are in a kitchen in Zone 2 deciding how to get to Paris, that number is missing most of the morning.

Our city-to-city time includes every leg on both sides:

Getting there — public transport at peak, from a central point to the airport or station.
Buffer — about 90 minutes before a short-haul European flight; 10–15 minutes on the platform for a train. Eurostar is the awkward middle: you need to be at St Pancras well before departure for security and border control.
The journey — scheduled flying time or train time, plus a realistic connection buffer if you have to change.
Getting into town — off the plane, passport control if it applies, bags if you checked one, then the trip from the terminal or station to a central point.

If the train needs a change, we do not assume the printed minimum. Overnight trains count as evening-out, morning-in, and we note when that replaces a hotel night.

A normal Tuesday

Best-case assumptions are how you get a useless comparison. We research each route under ordinary conditions:

Weekday — trains run closer to timetable; airports are busy in a predictable way.
Average weather — no fog, no thunderstorm hold, no miracle tailwind. We flag corridors where weather regularly wrecks the day.
One hold bag — this changes check-in and the wait at baggage reclaim.
A fare you'd actually buy — not the cheapest advance miracle, not the walk-up peak. Mid-band, booked a few weeks out.

We say when to fly

This is not a rail campaign. Stockholm to Rome is a fly. London to Barcelona is a fly. We say so. The four picks are Train, Flight, Depends, and Avoid — Avoid when neither option is a good use of a day, or the rail routing is a puzzle with no prize.

Depends is not a shrug. It means the answer actually flips — usually city centre vs an airport-side meeting, or whether you care more about hours or money.

Drafted with help, checked against the numbers

A writing assistant helps structure the route pages. The times in the comparison panels come from the data providers named on the page; the prose is checked against those stored facts before it goes up.

Numbers and prose are stored separately. A timetable update can replace the figures without the copy having to invent a new one.

Schedules get stale. We recrawl.

We check schedule sources weekly and publish a new snapshot only when the sample passes corridor-level quality checks. If a feed drops, we keep the last usable snapshot rather than guessing.

If something on the page is wrong, say so. Corrections get read, and credited in the revision history when that is useful.

What we measure

City-to-city minutes: Elapsed time from a central point in one city to a central point in the other, as above. Train and flight are both quoted this way.
Time in the air: Scheduled flying time from airline timetables, with no airport access, security or ground time folded in. We source this from ProFlightSearch.com.
CO₂ comparison: Carbon intensity from published European passenger-rail and short-haul aviation factors. Distance comes from rail geometry when we have it, otherwise a corridor estimate. Indicative, not a journey-specific footprint.
Fare bands: Low / mid / high, from prices seen booking 2–4 weeks ahead. Not live fares. Treat them as a planning range.
Frequency: Rough number of direct departures per day each way — how trapped you are if you miss one.
Transfer fragility: How badly a missed connection wrecks the day. Higher where one failed change means hours of waiting and no easy Plan B.
Disruption risk: Strikes, engineering, weather, or a known weak operator on that corridor — DB south of Padborg is the classic example.

What we leave out

Live prices — fares move by the minute. Use the operator, ProFlightSearch.com, or a comparison site for today's number.
Live seats — a route we call frequent can still be sold out on your date.
Your preferences — aisle vs a table, lounge access, points, fear of flying, motion sickness in the Alps. Real factors; yours to weigh.
Itineraries with three or more legs — once you are stitching that many trains, you are past what these pages are for.