It’s an age-old battle, and one in which both sides have a habit of obstinately refusing to admit that they could possibly be wrong. The question seems simple, but really isn’t: Which is the busiest station in the UK?

As ever with these things, it depends on which metric you use.

In the year straddling 2014-15, 99.2m entries and exits* were logged at London’s Waterloo station. That makes it the busiest station in terms of passenger numbers, which is admittedly a pretty solid measurement of how “busy” a station is.

By that metric, the busiest stations are all, fairly predictably, London termini. Victoria is the second busiest, with 88.3m journeys logged in 2014-15; Liverpool Street comes third with 63.6m; London Bridge and Charing Cross follow in fourth and fifth positions, with 49.5m and 42.9m respectively.

Birmingham New Street makes a surprise non-London appearance in 8th (35.3m journeys in 2014-15). But the remaining slots in the top 10 are filled, perhaps predictably, by Euston, Paddington, King’s Cross, and (okay, this one isn’t a terminus) Stratford.

“Woah there, buddy, hold up!” comes the cry from an alarmingly chummy reader. “Why does Clapham Junction have those signs up claiming to be Britain’s busiest railway station?”

Because, in a way, it is. In fact, it’s Europe’s busiest railway station by the same measure.

Every day, about 2,000 trains pass through Clapham Junction station, with about half of them actually stopping at platforms. In terms of the sheer numbers of trains that Clapham Junction sees, it’s an obvious winner (though it is perhaps surprising that no station in Europe can beat it).

With so many trains passing through, it’s no surprise that Clapham Junction wins by another measure, too.

In the past year, 28.4m passengers changed trains at Clapham Junction, making it the busiest station by interchange.

So, there you have it. Clapham Junction is the busiest station in Britain, but so is Waterloo. And so is Clapham Junction.

The more you know.

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*This figure excludes anyone who somehow managed to pass the gateline without a ticket, but also includes anyone who for some strange reason passed it without actually getting onto or off of a train. Anyway, it’s the best figure we have for passenger numbers.