JiaYuGuan is the first pass at the western end of the Great Wall of China.
It lies 6 kilometers southwest of the city of JiaYuGuan in GanSu province. The fortress lies between two hills and near to an oasis that was then on the western edge of China.
According to legend, when JiaYuGuan was being planned, the official in charge asked the designer to estimate the number of bricks required; the designer surprised the official by giving him an exact number. The official questioned his judgment, asking him if he was sure that would be enough, so the designer added one brick to the total. When JiaYuGuan was finished, there was one brick left over, which was placed loose on one of the gates, where it remains today.
Nearby are the DunHuang Caves (also known as the MoGau Caves); these grottoes date from the 4th century AD and contain Buddhist art from over the next thousand years.
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