Andrew Adonis – peer of the realm, arch remainer, former transport secretary, would-be Labour MP for Vauxhall – has been to Croydon. More than that he’s been thinking about Croydon, which is always dangerous. Here’s what he’s been thinking:

Some background, in the unlikely event you’ve landed on this story without knowing what “zone 4” means. Transport for London divides its tube and rail network into concentric fare zones. Zone 1 is the central business district, 2 & 3 are inner London, 4 to 6 are the suburbs. On selected routes beyond the official bounds of the capital, you’ll find stations in zones 7 to 9, as well as assorted lettered ones where the fares are weird, but that’s by the by: the rule, basically, is that the closer into the city you are, the lower the zone number and the lower the fare you have to pay.

Croydon, a south London/Surrey suburb that would be a sizeable city in its own right had it not long ago been swallowed by London, has two rail stations in its commercial centre. East Croydon is a stop on the London to Brighton line; West Croydon is served primarily by suburban services. Both are currently in zone 5.

On Adonis’ second point I tend to agree. The names East and West Croydon bug me for the faintly esoteric reason that

a) they’re both in central Croydon, and

b) phrasing them that way around suggests the two are a long way apart rather than about half a mile from each other.

Personally I’d go with Croydon East and Croydon West, but if local worthies want to call the bigger station Croydon Central then, well, fill your boots.

The other point, though, is more complicated. If you commute between central London and Croydon then it’s obviously in your interests to bring it down a zone as that’ll nudge it into a cheaper fare band. That, in turn, stands to benefit businesses who employ those commuters or are trying to attract south Londoners to spend money in the town.

Does it make sense, though? Is Croydon actually close enough to central London to justify being in zone 4?

To find out, I just spend an oddly therapeutic quarter hour measuring the distance between various important outer London centres and Charing Cross, the official centre of London. Here are the results, ranked by distance in miles, and with the fare zone included:

Logically, given the concentric nature of the London fare zones, you would expect the zone numbers to increase steadily as the distance from the city centre does, and for the most part they do. Not always, though: Kingston is marooned in zone 6 despite being a distance from Charing Cross more appropriate for zone 5.

Meanwhile, Epsom and Dartford, contiguous suburbs outside the Greater London boundary, fall out of the main system into the freaky outer zones, despite being closer in than Uxbridge. But Epping, several miles beyond the boundary and even outside the M25, gets to be in zone 6 because of a special arrangement between TfL and the local authorities.

There are several reasons for such oddities. One is that the idea Charing Cross is the centre of London is merely a useful fiction: London doesn’t really have a centre, so much as a lozenge-shaped central zone, running roughly three miles north to south and six east to west. Measurements from Charing Cross, convenient though they are, might be misleading.

Another is that Greater London itself is similarly unbalanced: that’s about 32 miles east to west but only 26 north to south.

Image: Wikimedia Commons, based on Ordnance Survey data.

A third is that its boundaries owe as much to the local politics of the early 1960s as they do to any rational sense of what London is. The only reason Epsom ended up outside, despite being an entirely suburban district surrounded by Greater London on three sides, is because the local Tories kicked up a stink half a century ago. (More on that here.) That, perversely, means higher fares for the locals today.

Anyway. You can make a case for Croydon being better placed in zone 4 than 5 but it isn’t an overwhelming one: Kingston has a far better case for promotion. Which is a bit of a wet conclusion, if I’m honest with you, but then again I really just wanted an excuse to play with a map.

Jonn Elledge is the editor of CityMetric. He is on Twitter as @jonnelledge and on Facebook as JonnElledgeWrites.

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