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For London cabbies battling Uber, the map is in the mind

London cabbies have to memorize every street in the city before they can get behind the wheel of a taxi. To them, it brings a critical advantage that GPS-wielding Uber could never provide.

London's black cabs are a crucial part of the city's character, on par with a double-decker bus or a "Mind the Gap" sign.

Hop in a taxi and your experience will typically feature the following: a chatty driver with opinions on almost everything, a route that takes what feels like a hundred turns, and no dashboard GPS device to guide the cabbie through the city's labyrinthine streets.

For all that, you can thank the Knowledge, a 153-year-old system for memorizing every street and landmark in a six square-mile area of central London. The Knowledge requires all cabbies to navigate between any two points in the city entirely from memory. Hopeful drivers study for three to four years, traverse London on a motor scooter to learn the shortest routes across town and are required to pass a series of intense oral exams -- all before they can get behind the wheel of a taxi. It's a process unmatched anywhere in the world.


Before you can drive one of these, you have to learn every street in London.

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Created in 1865 for horse-drawn carriages, the Knowledge has survived the automobile and London's explosive growth into a global city. These days, though, technology is presenting the Knowledge with new challenges. Anyone can access a GPS device to get around, and though they also ply London streets performing a similar job, Uber drivers don't have to learn the Knowledge to earn a license (they only have to pass a less stringent map reading test). Cabbies complain that makes for an unequal playing field, but the drivers I spoke with aren't fazed. They proudly defend the Knowledge and insist they couldn't do their job as well without it.

But that doesn't mean they're not adapting.


A student at the Wizann Knowledge school studies runs through London. 

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Back to school

To better understand how cabbies learn the Knowledge, I visited Wizann, a Knowledge school near London City Airport where hopeful cab drivers can get extra help. Dean Warrington, the school's founder and a former cabbie, let me attend an hour-long evening class. With its fluorescent lights and dull-patterned carpet, the classroom looks like any other. Except, that is, for the large maps of London on two walls, and, on top of each student's desk, another map covered in plastic film.

The purpose of the class is to review a few runs, or the routes through London that cabbies have to learn. Each student has a list of runs that were asked about during the previous day in appearances, or the one-on-one oral exams with the London transit authority that are part of the Knowledge process. Warrington calls out the first one: Willesden Junction to Angel Underground station. The 13 students (12 men and one woman) lean over their maps to trace the run with dry-erase markers.


As a fellow student traces his directions on a map, hopeful driver Jake Whincup calls out a run across southern London from memory.

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Next to me is Jake Whincup, a physical education teacher by day and Knowledge student by night. He talks for a few minutes with the student sharing his table about the best way to go, but when he settles on a route, he closes his eyes and slowly calls out the turns from memory. His focus is so powerful, I'm sure that if I could peer into his brain, I'd see synapses firing. It's mesmerizing to watch.

As Whincup works, Warrington stops to talk to another student, Hussein (he declined to give his full name). As they talk about whether it's best to always go over or under Regent's Park (always go under), Warrington gently corrects Hussein's first set of turns.


Wizann student Hussein draws a run that was called at an appearance the previous day.

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"Every run you take, the beginning and end are most important," Warrington says, drawing on Hussein's map. "You can't muck up the beginning."

Warrington then calls on a few students to plot their runs. When no one gets it exactly correct, he spills out the directions as casually as if he were a waiter rattling off salad dressing choices. A debate breaks out over whether you can turn left on a certain road (remember, you're driving on the left). Whinchup uses Google Streetview on his phone to check for sure.


At the Sherbet Knowledge school, Joe Pearson shows how students use a fabric cord to draw a straight line between two points.

Andrew Hoyle/CNET

Later, as he tracks a different run (Wandsworth County Court to Belsize Park Underground station), Whincup uses a fabric cord to draw a straight line between the two points. Warrington says the idea is to use that line as a guide when planning your run and try to keep as close to it as possible.

"The shortest distance matters," he says. "You can go further from the straight line as long as it's the shortest route."


Wizann founder Dean Warrington (left) urges his students to always take the shortest route between two points, even if it's not the fastest route. 

Kent German/CNET

The Knowledge at work

Hop in a black cab (they're officially called "Hackney Carriages") to see The Knowledge in action. Name your destination and you'll typically get a nod in response. True story: In the three years I've lived in London, I can count on one hand the times when the driver didn't immediately recognize where I wanted to go.

Even when you don't get an instant nod, the Knowledge quickly takes over. Rather than admitting outright that they don't know your address, London cabbies will ask questions to clarify. It's a common trick to narrow down the mass of the city to a specific area. A nearby major road is usually enough.


Any taxi ride in London involves many turns, but the goal is not to travel too far from a straight line between the origin and destination. 

Kent German/CNET

"I'll guarantee that with all my drivers, if I ask them to take you to any road in London, they will ask you one question: 'Where is that off?,"' says Asher Moses, a cabbie for 28 years and the CEO of Sherbet, a company that rents taxis and runs a Knowledge school. "That's all we need to identify that road instantly."

Mick Smith, a driver for 28 years, says that even for the tiniest lane, he needs to go there only once to remember it later. "When you're out on the road all the time, it sort of slots in. Getting there is never the problem, but the more information a taxi driver has, the better."


Taxi driver Asher Moses says that London without the Knowledge would be like London without the red bus. 

Andrew Hoyle/CNET

The Knowledge really kicks into gear once your ride starts. London cabbies can't go a few blocks without making a turn -- then another and another till you think you're going in a circle. They'll use the narrowest alleys, rail station approach roads and pretty much anywhere that the cab can fit to get to your destination.

If variables like road works or the ever-present traffic suddenly get in the way, they'll compute a new direction without having to ask a GPS screen. Sometimes, they'll tell you where they're going or ask if you prefer a specific route. As a passenger, it can be a challenge to relax and remember that a seemingly circuitous route doesn't mean that you're lost or getting ripped off. Sure, that can happen -- I had a ride recently where even I knew a shorter way -- but it's rare.


Though cabbies and Knowledge students occasionally use GPS and paper maps as a reference tool, their minds become their ultimate guides.

Andrew Hoyle/CNET

Keeping calm on a twisting ride is an understandable challenge for tourists, but the proliferation of mapping apps has caused even longtime Londoners to ask questions.

"Now with technology, you got people sitting in the back of the cab using Google Maps," Smith says. "And because you're not driving what it says on their thing, people say, 'Why are we going this way?'"


Cabbie Mick Smith says he needs to go somewhere in London only once to remember it later.  

Kent German/CNET

Technology as a tool

Even if it can make a passenger restless, GPS has emerged as a tool for some cabbies. Tony Norris, a cabbie for 31 years and a teacher at the Sherbet Knowledge school, will sometimes use it to initially locate an unfamiliar address before letting the Knowledge take over.

"I don't know every point in London and I don't know every street in London," he says. "But if [a GPS device] tells me a street that I don't know is near Fulham Broadway, I'll get you there. That's the difference for me -- I haven't got to sit there and drive with one hand looking at a map."


Joe Pearson stands in a classroom of Sherbet London's Knowledge school.

Andrew Hoyle/CNET

Joe Pearson, a hopeful cabbie currently studying the Knowledge at Sherbet, says that even though it isn't reliable all the time, he uses Google Maps to help learn new runs. "If I'm desperate and I need it, I'll take a quick look."

That's fine, Moses says, but replacing the Knowledge with a GPS device would change fundamentally London's character. "Taking away the Knowledge would be like taking away the black cab, the red bus and the telephone boxes," he says. "Eventually, yes, [taxis] might become electric vehicles without drivers, but until then I don't see a time without the Knowledge."

Smith says Transport for London, the city agency which administers the Knowledge, could change its scope to a smaller area of London, but it will always be relevant since it gives him a grounding that technology can't replace. "There's not a doctor or an attorney that doesn't use a reference book," he says. "People always talk about using GPS over the Knowledge, but if your phone doesn't work, you still have to have the basics."

Norris says killing the Knowledge would be a terrible thing. It lets cabbies deliver a level of service unmatched anywhere in the world, he says, both because they always know where to go and because the appearances teach them how to interact with passengers.

"Over the years there was talk about technology and computerizing [the Knowledge], but what they lose by doing that is they don't have the one-to-one scenario," Norris says. "It's how you deal with the public. If they want to call you a rotten old so-and-so, well, then you have to say to them, 'Well, my mother loves me, and that's all I worry about.'"  

London's taxi drivers send Uber a message

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Sit back and relax

Until driverless taxis really arrive, it's difficult to imagine London without the black cabs just as they are. It was a cold, rainy night when I attended Wizann, and I opted for a taxi over a longer Underground ride home. As I approached a taxi rank, the driver of the front cab rolled down her window. "Hop in, love," she said. "It's not a night for a walk, but it's warm inside."

I gave my Bermondsey address, but it was clear that my street, a two-block long lane not far from the River Thames, didn't immediately register. She asked a question to narrow down the location and then another. Still no go. But when I gave her the name of an adjacent major road, it's as if I could hear the gears of the Knowledge lock into place in her head.

"Of course," she said, "I know right where that is."

Minutes later we were on our way past Canary Wharf without a wrong turn. I just sat back and enjoyed the ride.

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