THE OLD OBSERVER

In one sense, it doesn't really make sense to compare capital cities with each other. Edinburgh is grand and genteel, London is grimy and shiny, and Cardiff is, well, as I said, a bit of a confusion.

After all, the only thing that links these places is the fact that at some arbitrary point in the past, somebody (usually a king or a warlord) chose to live there, built a massive castle, and everyone else knew that that was the place to be.

Due to the way the United Kingdom came together, Cardiff was the last of these established capital cities. In fact, up until 1905 it wasn't even a city at all! Which means of course, that it's only had just over a hundred years to figure out what kind of a city it truly is.

That doesn't mean it doesn't have history, of course. The Romans built a fort here to fend off the Celts (Silures) and hundreds of years after the Empire had abandoned Britannia, the Normans built a castle over the top of the ruins. Ever since, Cardiff has been growing along the river Taff.

I visited the castle yesterday. About two hundred years ago, the 3rd Marquis of Bute practically rebuilt it, and you can still see the past hidden in its stones. It's a motte and bailey castle, which means it has a keep on a mound, surrounded by a moat, right in the centre of it. It's well worth a visit, although some of the stone steps are incredibly steep and narrow.

The sun came out for a moment as I was standing on the top of the keep. The green below glimmered with shadow and the light caught the turreted walls. Beyond, the city glinted in the haze. I peered through the long slits in the stone and imagined myself firing arrows at invaders. It went misty again when I climbed back down to the green.

One of the most emotive things you can do in Cardiff Castle is walk around the inside of the walls. The walls themselves are about ten feet thick and so dank, dark, windowless corridors wind around the site. During the Second World War, they were used as air-raid shelters. There were still some narrow, wire-framed bunk beds propped up against the damp walls. I couldn't think of anything worse than having to sleep there listening to German planes pop-popping overhead. But of course, there was something much worse.

Next, after a very pleasant cup of tea, the open-top bus took me winding through the grand bits of the city I hadn't yet seen. The tour guide seemed intent on pointing out that all the buildings had dragons on the roof. Domes and pillars, porticos and engravings lined the route. Then, mysteriously, we were bouncing along by a grim-looking steelworks, black with smoke and age. Vehicle tracks had left huge puddles in the mud and grim-faced men in orange protective clothing stood pointing at something.

Beyond the steelworks, the bay spread out into the sea-mist. The fog was hiding the horizon, so docks turned into bay turned into cloud turned into grey. A vast boat, the Bro Deliverer was arriving. The tour guide said it was probably importing coal, after which she paused in a melancholy sort of way.

The docks are interesting. Once the heartbeat of Cardiff's shipping industry, they're trying hard to be the cool, new part of the city. If you like pizza, coffee, doughnuts, ice-cream, skateboarding, expensive opera or Doctor Who, then this is definitely the place to come. This is where the Wales Millennium Centre is of course, emblazoned with the six-foot-high windows that proclaim In These Stones Horizons Sing. I've been trying to work out whether that's more than just a few arty words that sound clever together or whether that really does mean anything.

I can imagine that in the summer, this is a really great place to be. I ate some fruit and waited for the bus.

I think I'm gradually getting more familiar with the city. There certainly is a lot going on, and clearly it's doing its best to transform and reinvent. It was interesting to me that I felt completely at home wandering around the castle green listening to Huw Edwards talk about the history of the place. Yet at the docks, the place that ought to be the shiny new hub of coolness, I was kind of stuck for something to do. 

I don't really know what this says about me - perhaps it's just another reminder that I'm not in my twenties. I also think there's a lot to be said for whom you're here with. Bath was an incredible place to be at university, but mostly because of my friends.

On this ongoing tour of capital cities, I'm dropping in like an outsider for just a few days each time, trying to pick up a flavour of the place. But it occurs to me that it's very different when you're in a strange city by yourself. Given a set of friends, and the flexibility of being young, I think I would have enjoyed university here back in the day.

As an old observer though, I'm not so sure.