Cheomseongdae
LocationSouth Korea
Year632-647
Size9.4 m tower
OperatorSilla kingdom
About Cheomseongdae
The oldest surviving observatory structure in East Asia. A tapered stone tower of 362 blocks, by one reading one for each day of the lunar year. Built in Gyeongju, capital of Silla, during the reign of Queen Seondeok. A designated national treasure of Korea.