Building the impossible

City at night
The hero of the modern skyline is the computer

Walk around any major city in the world and you'll find iconic buildings that simply couldn't have been constructed until just a few years ago.

Some are so admired by the public that they've gained affectionate nicknames: two famous examples are the Bird's Nest (the National Stadium) in Beijing and the Gherkin (30 St Mary Axe) in London.