Japanese architect Shigeru Ban has introduced a bridge over the Gardon river in France made entirely out of cardboard tubes. The bridge is made from 281 cardboard tubs and is strong enough to carry 20 people at a time.
Weighing 7.5 tonnes, the bridge is made from 281 cardboard tubes, each 11.5 centimetres (four inches) across and 11.9 millimetres thick. The steps are recycled paper and plastic and the foundations wooden boxes packed with sand.
It's an impressive achievement, but what happens when it rains? Or if somebody drops a cigarette? I could make a safer bridge out of sticks of dynamite.