Cheomseongdae, the Oldest Astronomical Observatory in the World

Located in the city of Gyeongju of Gyeongsangbukdo Province, South Korea, Cheomseongdae is the oldest living observatory in the world. It stands as one of the most monumental sites that reveal the importance of astronomy and astrology on the ancient Korean civilization. Roughly translates to the ”star-gazing tower (Atlas Obscura)” or the ”reverently regarding the stars platform (Cartwright),” Cheomseongdae was constructed during the reign of Queen Seondeok (r. 632-647 C.E.) in the Silla Kingdom and was designated as South Korea’s 31st National Treasure on December 20, 1962.

 

The cylindrical tower stands 9.17m (30ft) high and 5.35m (17.5ft) wide at the base. The numerical significance embedded in the stones is also a popular topic of scholarly research. The 362 granite stones of the Cheomseongdae are believed to represent the 362 days in a lunar year, and the 27 layers of stones piled up to allude to Queen Seondeok, who was the 27th monarch of the Silla Kingdom; the twelve layers below and above the window of observation were also claimed to symbolize the twelve months of the year and the Zodiac signs.

 

From an architectural standpoint, the structure of Cheomseongdae is indeed remarkable and unprecedented. Scholars claim that the placement of the rocks like the Chinese character ‘井’ (jeong), the soil which fill the inside, and the position of the window space were all designed under great consideration for function and stability. The soil, in particular, is thought to be included to preserve the circular shape and minimize the effects of earthquakes.

 

Cheomseongdae is believed to have been built in the reign of Queen Seondeok as an observatory, while other theories suggest it may have been designed to worship Buddhism. Other studies note that the tower mimics the female form and could have been dedicated to worship Queen Seondeok. Much of Cheomseongdae’s history remains a mystery, but most scholars agree that it was a site of astronomical research.

 

Written by: Yini Lin.

From Hawaii, United States. University of Hawai’i at Mānoa Class of 2021. B.A. Candidate in Korean Language Flagship. B.A. Candidate in Asian Studies. Exchange student at Korea University. Intern at VANK (Voluntary Agency Network of Korea)