Cheomseongdae Observatory

It was one of the best trip I had. It’s a beautiful place, very historic and reach in Culture. The view is stunning.

2025.03.31 Spring at Cheomseong Observatory and its surroundings. Nice place to see cherry blossom. Walking distance to many attractions.

Cheomseongdae, located in the city of Gyeongju in South Korea, is widely regarded as the oldest existing astronomical observatory in East Asia, and one of the oldest in the world. Built during the 7th century under the reign of Queen Seondeok of the Silla Kingdom, Cheomseongdae reflects the remarkable scientific knowledge, cultural advancement, and philosophical thought of ancient Korea. Though modest in size, this stone tower has stood the test of time for over 1,300 years, silently witnessing the rise and fall of dynasties and civilizations. It remains a symbol of Korea’s early pursuit of science, astronomy, and harmony with nature. The name Cheomseongdae is composed of three Chinese characters: “cheom” meaning to observe, “seong” meaning stars, and “dae” meaning tower. Together, the word translates to “star-gazing tower,” which describes its intended function. Though it may look like a simple stone structure, it holds a great deal of mathematical and symbolic meaning. Cheomseongdae is approximately 9.4 meters tall and constructed from 362 pieces of cut granite. Many scholars believe this number represents the days in a lunar year, which was the basis of timekeeping during the Silla period. One of the most striking features of Cheomseongdae is its shape. It is constructed in the form of a gently curved cylinder that becomes slightly narrower in the middle, resembling an hourglass or an upside-down bottle. This design not only gives it a unique and elegant appearance, but also provides structural stability. Despite Korea’s history of earthquakes, Cheomseongdae has remained intact for over a millennium. The observatory rests on twelve square stones arranged in a circle, which are thought to symbolize the twelve months of the year or the twelve signs of the Eastern zodiac. The tower consists of 27 layers of stones above the base, which is widely interpreted as a tribute to Queen Seondeok, who was the 27th ruler of the Silla Kingdom and the first reigning queen in Korean history. This detail reveals how the structure served not only as a scientific instrument, but also as a political symbol of her leadership and vision. There is a small square window located about halfway up the tower. Historians believe that astronomers of the Silla kingdom entered through this window, using a ladder to climb inside. From within the observatory, they would study the movements of stars and celestial events to determine seasonal changes, track lunar cycles, and predict weather patterns. In ancient agricultural societies like Silla, such information was essential for ensuring the success of crops and maintaining order in the kingdom. Accurate astronomical knowledge was also seen as a sign of a wise and harmonious government. Cheomseongdae’s purpose was therefore both practical and symbolic. On a practical level, it helped Silla’s leaders make decisions about agriculture and the calendar. Symbolically, it represented a connection between the heavens and the ruler, emphasizing the idea that a wise leader ruled in accordance with cosmic order. The fact that it was commissioned under the reign of a female monarch makes it even more remarkable, as it demonstrates Queen Seondeok’s dedication to intellectual and scientific progress during a time when many rulers focused only on military or territorial power. Today, Cheomseongdae remains an iconic cultural and historical landmark. It is listed as National Treasure No. 31 of South Korea and is part of the UNESCO World Heritage Site designated as the Gyeongju Historic Areas. Visitors from around the world come to see this elegant stone tower and learn about the scientific and cultural achievements of ancient Korea. At night, the tower is beautifully illuminated, making it a popular site not just for tourists but also for local residents. Nearby, other historical landmarks such as burial mounds, palaces, and temples provide a fuller picture of Gyeongju’s importance as the capital of the Silla Dynasty.

We went on a public holiday and predictably, the place was full of tourists. It was an enjoyable walk. A lot of cafes surrounded the area and it was well-lighted.

This is one of Korea’s prides and national treasures as it’s the oldest observatory in Asia. It’s beautiful during the day and has a beautiful nightscape too. They light up the tower with several different colors and there were busking performances. It’s also free to visit; idk why it talks about tickets below.

Small but proud star gazing observatory in Gyeongju. The site was not big and took about 10 minutes on foot from the Tomb Complex. There was a sign explaining is structure, how it was built. A nice place to make a short stop while exploring the city of Gyeongju.

While it may not look as tall as you might expect or have the "wow factor" people crave, it's well worth the visit because it's an important and special structure. It is the oldest astronomical observatory in Asia and is believed to have been constructed between 632-647.

Interesting historic place, but veer off to the right and you’ll get some great photo opportunities nearby the sunflower garden :)