The cultural and historical city of Danyang (丹阳) was one of the fifteen counties designated by the Qin Dynasty in 221 BC. At that time it had been called Quhe and later Yunyang. In Chinese, alder tree is read as chiyang (赤杨), which means red poplar, chi (red) can also be written as dan (丹), yang (杨/阳) as "the sun". During the Tang Dynasty there had been a lot of alder trees growth here, so since the year 742 AD the city had been renamed Danyang. It was the hometown of the two great emperors of ...