Baphuon

Baphuon was once a large, five-tiered pyramid, built in the 11th Century. It was built as a "Golden Mountain" by Udayadityavarman to be legendary. It has been under restoration since 1908 by the French - many countries are helping with various sites - and it is not possible to actually enter the temple, the only one where this is the case. This temple demonstrates the massive task of restoration better than anywhere else. They began by removing damaged stone blocks, carefully cataloguing the location of each and every piece. Then the Khmer Rouge came along (remember those guys). One of their practices was to destroy writings and records of any sort, so now the restorers are left with the world's largest, heaviest and most delicate jigsaw puzzle. Much of the temple is covered with tarpaulin, but the walk down the stone tier is worthwhile. The tier is raised above a man-made pond (which actually has little water left in it) and is about a quarter-mile long.