In pictures: Three Gorges trials

1 of 6 The boat lock on China's flagship Three Gorges Dam has undergone its first trials in a glare of publicity.

2 of 6 The five-tier lock- said by China to be the world's biggest - is built to take boats of up to 3,000 tonnes.

3 of 6 The lock was being tested ahead of its scheduled opening to all shipping on 20 June...

4 of 6 ...when vessels will be able to pass from the Yangtze river into the Three Gorges.

5 of 6 There is a mood of relief at the dam, but work will go on until 2009 when it should achieve its target water level.

6 of 6 At the same time, the existing structure is already showing faults, with China admitting to 80 cracks to date.