Look! A tram! Here’s another:

Melbourne. Image: Getty.

My god, they’re everywhere!

Manchester. Pleasing that all these cities start with M, isn't it? Image: Getty.

In all, according to this helpful and informative guide by the Prague transport authorities (in Czech) there are 265 active tram systems in Europe. Which is quite a lot of trams.

In some countries, though, there are a lot less than there once were. As anyone who’d seen Who Framed Roger Rabbit will know, in the 1950s, the “streetcar” networks that had fuelled the growth of American suburbia were ripped up to create more space for the motor car. British tram systems generally died at the same time.

And, the thing is... it’s not immediately obvious that this was the wrong decision. Trams, after all, are basically less flexible buses: they take up space on roads, they’re relatively low capacity, and you can’t make them go where you want.

Except – people love trams, don’t they? If they were talking about building a new tram line near your home, then you’d probably be quite excited about that. If they were talking about a new bus route? Well, probably not so much.

So what gives? Are trams really just, as the Economist Explains once explained, “a waste of money”? Or is there some rational reason for our attachment to them?

Two rails good, no rails bad

First, let’s run through the case for trams.

They’re visible

You can tell if a tram line runs down the street you’re standing on: there will be subtle hints, like the massive steel rails in the road. Permanent lines are more likely to encourage permanent stops and network maps. And, as the entire existence of Citymetric has served to prove, it’s the maps people get excited by.

So, if you want legibility in your transport system, trams, not buses, are the way to go.

They can’t be removed on a whim

Okay, they’re harder to build – but that’s actually a plus, in its way. Rails have an air of permanence that bus routes lack. That makes it easier for residents to plan journeys, employers to decide where to base themselves, and so forth, without worrying that the transport links they rely on are suddenly going to vanish.

They’re cleaner

No spewing out exhaust fumes, at least in the city itself. (If they take their electricity from fossil fuel power stations, they may be doing it elsewhere, of course, but still.)

They’re easier to segregate

Which is good as it means they’re less prone to disruption by things like traffic jams.

Okay, technically you can achieve this by segregating bus lanes, too... but those are pretty easy to undo, and the authorities are likely to come under pressure to undo just that. (After all, why should one category of vehicle get special treatment, just because it’s way more efficient?) A segregated tram route is likely to stay segregated.

Oh, and you can give them priority at signals, too. All of which means...

They’re faster and more predictable

None of this “getting stuck in traffic for ages and then turning up in groups of three”. Passengers can be reasonably certain that, when the information board says there’ll be a tram in five minutes, there’ll be a tram in five minutes.

They’re more comfortable

Stand on a bus, and you risk getting thrown all over the place as every time it brakes sharply. But trams tend to brake and accelerate more gently, so you’re relatively comfortable, even if you’re standing the whole way.

Oh, and you can extend trams by adding extra cars during rush hour, without clogging the road or hiring more drivers. Try doing that with buses.

So, they’re higher capacity, too.

Look, they’re just better, alright?

Trams are seen as good for regeneration and place-making – partly because they encourage development, partly because building them is so expensive and complicated that it often ends up used as an excuse to achieve those things.

But also because they are just cooler. The bells! The whirring sounds! The screeching noise they make when they go round corners! How many times have you gone to a strange city and found yourself thinking, “Oooh look, a bus”? Unless you’re a tourists visiting London for the first time, I’m going to guess the answer was: never.

Trams, though. Trams are brilliant.

Two rails good, no rails better

Except, are they? Because they also come with some downsides.

They can’t be removed on a whim

Once you’ve put in a tram, you’re stuck with it. If you mucked up the planning and it goes to slightly the wrong place? Well, tough. Too expensive to change it.

They don’t mix well with bikes

Don’t get stuck between rail and pavement if you value your continuing existence.

They take up too much space

To get most of the advantages listed above you need to give trams segregated road space – and space is at a premium in most cities.

So: trams come with a huge opportunity cost. A tram lane is something you can’t use for something else.

They can’t move around obstacles

Trams are great if you can segregate them properly. But sometimes you can’t – see above – and when that happens you’re stuffed. They’re on rails, so can’t move around blocks in the road. A bus, with difficulty, can.

The big downside, though, is:

They cost a fortune

You have to lay new track. You have to redesign roads. Then you have to buy the vehicles, which generally cost more than buses. Oh, and they may be more expensive to run (research on this seems to vary).

Why bother, when you can achieve most of the same transport goals with a fleet of buses?

Well – I explained why you’d bother above. There are good reasons for it. But whether there are enough good reasons is going to depend not just on the circumstances in every individual city, but on the political and economic cycle too.

Trams are brilliant. But you don’t have to look far for reasons why they declined in some countries – or why they’ve been so slow to return.

Still, trams, eh? Phwoar.

Jonn Elledge is the editor of CityMetric. He is on Twitter, far too much, as @jonnelledge.

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