h2g2 The Hitchhiker's Guide to the Galaxy: Earth Edition

Rather than do something transient for the millenium like a dome or big wheel, Cardiff took the opportunity to upgrade the national stadium.

What was created was the first retractable roof stadium in the UK. An ideal settingfor the fianl of the Rugby world cup and the ideal auditorium to let the Welsh voices cheer and sing on their football and rugby playing heroes.

It is also THE most futuristic looking building on the planet. It honestly looks as if it has recently landed from outer space, and is trying to work out why everyone is staring at it in a kind of "Good God, what is that?".
It is also near the largest pub in Britain, namely The Prince of Wales (A Wetherspoons unfortunatley)

The stadium is one of only 2 in the World with a removable pitch, the turf resting on removable square pallets. The other one I believe is in New York.

The Prince of Wales is not the largest pub in Britain to my knowledge. In fact I think even Wetherspoons claim to have a larger pub elsewhere in the UK.

They used to claim that the Wetherspoons in Manchester (the Deansgate one) was the biggest.

The prince of Wales WAS the biggest pub in Britain the last time I talked to the manager. It is bigger than Deansgate by a couple of square yards.

For another futuristic building in Wales, how about the Great Glass House at the new National Botanic Gardens of Wales - its the biggest single span greenhouse in the world, and is expected to last for up to 100 years.http://www.gardenofwales.org.uk/direct.htm

Which is 99 years longer than the Dome in London!

(I know it's not related to Cardiff, but it's only about an hours drive!)