Why do the signs at King's Cross St Pancras, London's biggest tube station, seem to take you the long way round?

Get lost. Image: Oxyman at Wikimedia Commons.

Kings Cross St Pancras Underground station is, as you'll know if you've been inside it, a bit of a nightmare. The clue is in the name: the station serves two mainline stations which, while close together, cover a vast area above ground between them – and an even vaster network of underground tunnels. As a pedometer user, I can vouch for the fact that the walk from Thameslink to the Piccadilly line represents a good fifth of your daily steps. 

The six tube lines and two train stations also make the station very busy, which can make navigating its hundreds of metres of tunnels even more difficult. Even before you get inside, the station has 11 entrances.

This is the best overview map I've been able to find of the station: each entrance is marked with the Underground symbol: 

In the centre is the "Tube ticket hall", which is the older, original ticket hall. Over time, bits and pieces have been added to it: a western ticket hall, serving the front of St Pancras International; and more recently, the Northern ticket hall, which stretches out towards the main, non-Eurostar bit of St Pancras. 

But there's a minor controversy surrounding all these ticket halls. That's because the station's signage sometimes points you along a route that isn't necessarily fastest.

To reach the Piccadilly and Victoria lines, for example, the signage directs you to the northern ticket hall – when actually it is quicker to go via the older ticket hall for example (to do so, follow the signs for the Metropolitan, Circle, and Hammersmith & City lines). The internet is littered with "hacks" to make your trek between lines a little shorter. 

So is the station really designed to slow you down? Is there a conspiracy against the blue lines? And do those hacks really work?

I called up Mike Guy, station manager at Kings Cross St Pancras, to find out. 

CityMetric: So why is the station so complicated?

Mike Guy: It's worth looking at the background here. When the Underground was first built, the earliest platforms were those now served by the Circle, Hammersmith and Metropolitan lines, all of which are “sub surface” [much less deep than, say, the Northern line]. 

What's happened is that over the years, as different lines have been constructed, the station has expanded, especially at lower levels. Recently, it's expanding further for two reasons. One is the Eurostar and St Pancras station. Then, in 2012, there was the introduction of the northern ticketed hall. 

CM: What's the best way to navigate it?

MG: Customers who know our station will choose the entrance with the most direct route to their line – our commuters tend to know by now which one that is. But for customers who don't know the station, the sheer size and the number of lines can make it quite confusing.

CM: So ideally everyone would use the best entrance for their line?

Right. We've signed as best we can, but if you enter from the north of the station, say, the walk to the Victoria line is quite a distance.

As a rule of thumb, the western part of the station, near St Pancras, is a good place to enter for the Metropolitan, Circle, and Hammersmith Lines. The Pentonville Road entrance is quickest for the Victoria line, but only during its opening hours (07:00 to 20:00, Monday-Friday). At other times, use the Euston Road entrance for both Victoria and Piccadilly lines, which is the smallest entrance and was the main station entrance for a number of years.

And for the Northern line, it's best to go via the newest entrance, or the north ticket hall, right next to King's Cross main line station. 

In case that's hard to visualise, here's a map showing which entrance to use:

CM: Why do some routes seem to send you a less direct route – like those that send you away from the old ticket hall for the Victoria and Piccadilly lines?

MG: We encourage people to use the subway which is at a lower level [marked above as the long pinkish tunnel running from the Victoria line to the Northern ticket hall] for transfers between lines. In general, that's fairly reasonable.

CM: That does mean you'd be walking for longer, depending on the transfer you're making – but is that to try and alleviate crowding? 

MG: Yes. And occasionally, to avoid congestion, we will divert passengers onto a longer route. 


CM: What could be done to improve things?

MG: We're continually trying to improve our signage and looking for feedback as to what could be different. I've been here for about four years, and I'm still interested to hear peoples' views on what we could do differently.

But I'm also very cautious - it's important that we don't make our signage too busy. Hopefully, passengers do find their way raound the station, but they'll occasionally choose a route that's slightly longer.

If you were to design the station from scratch, it wouldn't look like it does today. It's huge – that's why I enjoy working here. But it can be very disorientating.

* * *

So there you have it. Mike is right about the entrances: the best way to avoid the snare of tunnels is to bypass them before you even descend.

But we'd like to add a rule of thumb of our own: if you're already underground, head to the old ticket hall (from where you can access all lines*) by following signs for the Metropolitan, Circle and Hammersmith & City lines to avoid the special congestion-reducing line-changing tunnel Mike mentioned. Though don't tell too many of your friends. 

 

*You can actually access the Northern line directly from this ticket hall using a lift, though the walking access is cut off at the moment.  But maybe still better to head to the north ticket hall for the Northern line. Probably. This is getting too confusing now. I'm out. 

 
 
 
 

The mountain in North Wales that tried to stop the UK’s blackout

Elidir Fawr, the mountain in question. Image: Jem Collins.

Last Friday, the UK’s National Grid turned to mush. Not the official term perhaps, but an accurate one after nearly one million people were left without power across the country, with hundreds more stranded at train stations – or even on trains (which isn’t nearly as fun as it might immediately sound). 

Traffic lights stopped working, back-up power failed in hospitals, and business secretary Andrea Leadsom launched an investigation into exactly what happened. So far though, the long and short of it is that a gas-fired power station in Bedfordshire failed just before 5 o’clock, followed just two minutes later by Hornsea offshore wind farm. 

However, amid the resulting chaos and inevitable search to find someone to blame for the outage, a set of mountains (yes, mountains) in North Wales were working extremely hard to keep the lights on.

From the outside, Elidir Fawr, doesn’t scream power generation. Sitting across from the slightly better known Mount Snowdon, it actually seems quite passive. After all, it is a mountain, and the last slate quarry in the area closed in 1969.

At a push, you’d probably guess the buildings at the base of the mountain were something to do with the area’s industrial past, mostly thanks to the blasting scars on its side, as I did when I first walked past last Saturday. 

But, buried deep into Elidir Fawr is the ability to generate an astounding 1,728 megawatts of electricity – enough to power 2.5 million homes, more than the entire population of the Liverpool region. And the plant is capable of running for five hours.

Dubbed by locals at the ‘Electric Mountain’, Dinorwig Power Station, is made up of 16km of underground tunnels (complete with their own traffic light system), in an excavation which could easily house St Paul’s Cathedral.

Instead, it’s home to six reversible pumps/turbines which are capable of reaching full capacity in just 16 seconds. Which is probably best, as Londoners would miss the view.

‘A Back-Up Facility for The National Grid’

And, just as it often is, the Electric Mountain was called into action on Friday. A spokesperson for First Hydro Company, which owns the generators at Dinorwig, and the slightly smaller Ffestiniog, both in Snowdonia, confirmed that last Friday they’d been asked to start generating by the National Grid.

But just how does a mountain help to ease the effects of a blackout? Or as it’s more regularly used, when there’s a surge in demand for electricity – most commonly when we all pop the kettle on at half-time during the World Cup, scientifically known as TV pick-up.

The answer lies in the lakes at both the top and bottom of Elidir Fawr. Marchlyn Mawr, at the top of the mountain, houses an incredible 7 million tonnes of water, which can be fed down through the mountain to the lake at the bottom, Llyn Peris, generating electricity as it goes.


“Pumped storage technology enables dynamic response electricity production – ofering a critical back-up facility during periods of mismatched supply and demand on the national grid system,” First Hydro Company explains.

The tech works essentially the same way as conventional hydro power – or if you want to be retro, a spruced up waterwheel. When the plant releases water from the upper reservoir, as well as having gravity on their side (the lakes are half a kilometre apart vertically) the water shafts become smaller and smaller, further ramping up the pressure. 

This, in turn, spins the turbines which are linked to the generators, with valves regulating the water flow. Unlike traditional UK power stations, which can take hours to get to full capacity, at Dinorwig it’s a matter of 16 seconds from a cold start, or as little as five if the plant is on standby.

And, designed with the UK’s 50hz frequency in mind, the generator is also built to shut off quickly and avoid overloading the network. Despite the immense water pressure, the valves are able to close off the supply within just 20 seconds. 

At night, the same thing simply happens in reverse, as low-cost, surplus energy from the grid is used to pump the water back up to where it came from, ready for another day of hectic TV scheduling. Or blackouts, take your pick.

Completed in 1984, the power station was the product of a decade of work, and the largest civil engineering project commissioned at the time – and it remains one of Europe’s largest manmade caverns. Not that you’d know it from the outside. And really, if we’ve learned anything from this, it’s that looks can be deceiving, and that mountains can actually be really damn good at making electricity. 

Jem Collins is a digital journalist and editor whose work focuses on human rights, rural stories and careers. She’s the founder and editor of Journo Resources, and you can also find her tweeting @Jem_Collins.