How do metro systems cope with whopping great hills?

Barcelona has hills of the sort that are a right pain when you're planning a metro system. Image: Hedwig Storch/Wikimedia Commons.

Sudden steep hills are a bit of a pain in the arse  an engineering challenge for yer bog standard metro system.

Obviously you don't want too many steps between underground platforms and a station entrance. But long lifts will constrain the number of people who can get in and out, and could lead to over-crowding during peak hours; while escalators, nifty as they are, require a lot of space that isn't necessarily available.

So, how do you get people from the top of a hill to an underground train and back? Cities have come up with a variety of solutions to link their metro networks up with their more mountainous areas. Here are three.

1. The funicular

In Paris, the metro lines skip the top of Montmatre altogether, and deposit passengers in the streets below. If you really want to visit Sacré-Cœur without climbing a whopping great hill, there's this:

The Montmatre Funicular. Image: Anthony Atkielski/Wikimedia Commons.

Funiculars, for those who haven't had the pleasure, are cable-pulled cares clinging to the sides of steep slopes. As the cable winches one car up the tracks, it simultaneously lowers another, which provides a counter balance and reduces the energy the system needs. It's the sort of thing English resort towns use to carry old people up cliffs, and it's rather clever.

That said, in Paris the base station isn't anywhere near a metro station either, which is a bit off. Other cities make more effort to integrate their funiculars with the rest of their transport system. In Barcelona, the funicular that carries passengers up Montjuïc starts from what is essentially a platform within Paral·lel Metro station:

The lower platform. Image: YMblanter/Wikimedia Commons.

How it looks on the metro map. Image: TMB.

Naples has no fewer than four funiculars, three of which connected at a single station, Vanvitelli. The largest of these, the central funicular, carries over 10m passengers a year through its four stations. (By way of comparison, London's smallest tube line, our old mate the Waterloo & City, carries 15m.)

2. The cable car

Cable cars have picked up a bit of a rubbish reputation in certain western cities (can't think why).

In many hilly Latin American cities, though, they've proved really handy. They're relatively cheap and easy to construct, and bother quicker and less prone to disruption than buses.  Consequently they've popped up, in Medellin:

Image: Raul Arboleda/Getty.

In Caracas:

Image: AFP/Getty.

And in Rio:

Image: Mario Tama/Getty.

Oh, and you can use them as an alternative way of Barcelona’s Montjuïc, should you so wish.

There's one big downside to both cable cars and funiculars, though: they're not that big. Look at the size of the cars. They simply can't carry that many people compared to a traditional metro system.

So that leaves:

3. Clever station design

Okay, this isn't always an option, for all sorts of reasons. But some metro stations have been designed specifically to deal with the fact they're buried under massive great hills

Take Casco Viejo station, in the middle of Bilbao. It serves both a main line station, to the east, and the medieval heart of the city to the west (the name literally means “old city”). Between those two destinations lies the lower slopes of a huge hill which leads up to the Parque Etxebarria.

It'd obviously be pretty impractical to stick the station itself in the park, and get everyone to walk down. So instead, the metro platforms are buried deep under the hill, and connected to the world either side through long tunnels containing moving-walkways. You can just see the western one in the background here. It’s the big dark tunnel:

Image: Google Streetview.

El Coll–La Teixonera, in Barcelona’s hilly northern suburbs, does something similar. The deepest station on the network, it contains no fewer than 12 moving walkways, giving passengers a choice of slopes to pop out on. The eastern entrance to the station is a whole quarter of a mile away from the western one.

Then, to help locals with the last climb to their house, it offers outdoor escalators like this:

Image: Jonn Elledge.

Or, I guess, you could walk.

Jonn Elledge is the editor of CityMetric. He tweets as @jonnelledge.


Where did London’s parakeets come from?

Parakeets in the skies above Wormwood Scrubs, west London. Image: Getty.

Visitors to London’s many green spaces would have to be stubbornly looking at their feet to not see one of the UK’s most exotic birds.  Dubbed “posh pigeons” by unimaginative Londoners, these brilliant green parakeets stand out among the fauna of Northern Europe’s mostly grey cities.

‘Parakeets’ is actually an umbrella term referring to the multiple species, which can now be found in London, Amsterdam, Brussels, Paris and various German cities. By far the most common is the Indian ring-necked parakeet, easily recognisable by the stylish red ring around their neck, a matching red beak and, of course, the loud squawking.

In the last 50 years these migrants from South Asia have arrived and thrived, settling into their own ecological niche. In the UK, London is a particular stronghold, but although they may have originally settled in the leafy streets of Twickenham, the birds can now be found in cities as far north as Glasgow.

The story of how they ended up in London is a matter of some discussion and plenty of myth. One often reported theory is that the capitals’ current population are the descendants of birds that escaped from Shepperton Studios during filming of The African Queen, starring Humphrey Bogart and Katharine Hepburn. Others would tell you that they escaped from Syon Park in the early 1970s, when a piece of debris from a passing plane damaged the aviary and allowed them to escape. This chimes with their original concentration in South West London.
My favourite story by far is that they were released by Jimi Hendrix on Carnaby Street in the late 60s. Bored of London’s grey skyline, he set the little fellas free to liven up the place.

However they got here, from 1970 onwards their numbers boomed. In 1992, 700 birds were recorded in London Bird Report. By 1998, 2,845 were seen in the London Area, and by 2006 the ring-neck parakeet was 15th most sighted bird in London.

Darwin would be proud at how well they adapted to the new environment. Toughened up by the hard Himalayan climate, they handle the cold northern European winters better than most locals. Global warming is often brought up in discussions of the parakeets, but it is certainly only part of the story.
It helps, too, that the birds have a 35 year lifespan and few local predators, enabling them to breed freely.

As with any new species, the debate has raged about whether they are harmful to the ecosystem. Strangely reminiscent of the debate over human migrants, often the birds have often been accused of stealing the homes of the natives. The parakeets do nest in tree cavities also used by jackdaws, owls and woodpeckers – but there is little evidence that native species are being muscled out. 

The also provide a food source for Britain's embattled birds of prey. Owls and peregrine falcons have been know to eat them. Charlie and Tom, two city dwelling falcons monitored by Nathalie Mahieu, often bring back parakeets as food.
Of more concern is the new arrivals’ effect on plants and trees. By 2009 their numbers in the UK had grown so much that they were added to the “general licence” of species, which can be killed without individual permission if they are causing damage.

And Parrotnet, am EU funded research project studying the development of parakeet populations across Europe, has warned of the risk they pose to agriculture. In their native India, the parakeets are known to cause widespread damage to crops. As agriculture develops in the UK in line with warmer climates, crops such as maize, grapes and sunflower will become more popular. In India the birds have been documented as reducing maize crops by 81 per cent.

So the parakeets remain divisive. Environmentalist Tony Juniper has disparagingly described them as “the grey squirrel of the skies”. By contrast, the University of York biologist Chris D. Thomas has argued that the parakeets should be left free to move and breed. He sees those wary of the parakeet boom of “irrational persecution” of the bird.

For good or ill the parakeets are here to stay. As so often with migrants of all kinds, there has been some unease about the impact they have had – but the birds, popular amongst Londoners, certainly add colour to the city. Thriving in the urban environment thousands of miles from their natural habitat, they are a metropolitan bird for Europe’s metropolitan cities. 

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