THE TAXIS are breeding. There's no other explanation.

Feral cabs are creeping into the bushes and coming out with coy smiles and a litter of minicabs.

How else can we account for the clot of traffic that forms at Sevenoaks Station from about 5 to 7pm Monday to Friday? The jam builds up because there are far too many taxis for the spaces in the station forecourt.

So surplus taxis sit in the road, flashing their indicators and blocking everything behind them for miles.

Coming down Tubs Hill, drivers trying to squeeze past at the lights are often foiled by finding the yellow grid awash with cabs (the unspoken rule on yellow boxes, of course, is that it's OK to be on them as long as you're clearly indicating your intention to be off them, just as soon as the other motorists shift out of the way).

There's only one thing that can unblock this, apart from a squadron of traffic police with lifting machines.

That one thing is the 18.04 from Charing Cross, bulging with tired, taxi-craving commuters.

It's fascinating to speculate whether one set of stuck points would lead to hundreds of Sevenoaks drivers spending the night outside the pet shop.

("It's a 7-series, Sophie! I'm not leaving it on the main road all night! Anyway, where would I get a taxi?")

Well, the place to get a taxi is certainly not in the centre of town.

Despite the fact that there are several bits of road alluringly marked out for taxis only, the one thing you can guarantee never to see there is a cab.

The taxi zone in the High Street is a useful stop for private cars and road repair machines, but even when it was smack outside the Iceland store – where customers would stagger out hauling a year's supply of oven chips – there was never a taxi in sight.

The cabs were all down at the station waiting for the serious money.

Now, this concentration of cabs always puzzles me because I've yet to meet a single commuter who admits to taking a taxi home.

Every train traveller I know claims to walk, jog or cycle (rollerblades have been mentioned) to get home from the station.

Even people who live in places where the gardener's greatest enemy is sheep ingression insist that they're entirely self-propelling.

("Weald? Ten minutes, tops. Fifteen if the snow's deep.")

But clearly those taxis are being taken, because every time a train rolls in, the traffic clot unblocks and cars as far north as the Riverhead roundabout lurch into first gear with whimpers of relief.

I'm thinking that the people sliding into those taxis aren't from Seal or Godden Green at all. They're from places so close to the station that the taxi driver says "Where? Are you having a laugh?"

Yes, all those taxis are bustling off to St Botolph's and South Park and then nipping back within minutes to take up position on the yellow grid.

At least it keeps them out of the bushes.