By Guy De Launey
BBC News, Phnom Penh
Archaeologists in Cambodia have completed the first part of what has been called the world's largest jigsaw puzzle.
The 400sq km (154sq mile) Angkor site is world famous
The Baphuon, one of the largest and oldest temples at the world-famous Angkor complex, has been in hundreds of thousands of pieces for decades.
Under the Khmer Rouge's brutal regime, the plans for the temple's reconstruction were destoyed.
But now, after years of hard work, one section is reopening to the public.
A French-led team of archaeologists have been scratching their heads since peace returned to Cambodia in the early 1990s.
Almost 50 years ago, the crumbling temple was taken apart, so it could be strengthened and rebuilt.
But the numbers marked on each stone became meaningless when the plans were lost.
At first, a computer programme tried to make sense of the jumble of masonry around the site.
But ultimately the team have relied mostly on their own judgement.
Some of the Cambodian stonemasons worked on the original project in the 1960s.
Now tourists will be able to enter part of the temple for the first time and watch the ongoing restoration work.
It should be complete within two years.