Cheomseongdae Observatory

Cheomseongdae is the oldest existing astronomical observatory in Asia. Constructed during the reign of Queen Seon-deok (632-647), it was used for observing the stars in order to forecast the weather. This stone structure is a beautiful combination of straight lines and curves, and was designated as National Treasure No.31 on December 20th, 1962. Cheomseongdae was built in a cylinder shape with stones 30cm in diameter. 362 stones were piled up to make 27 levels. Roughly 4.16m up from the bottom there is a 1㎡ square entrance and a space to hang a ladder under it. The inside is filled with soil up to the 12th level, and the 19th, 20th, 25th, and 26th levels all have long rocks hanging on two areas, shaped as the Chinese letter '井' (jeong). It stands 9.17m high and the base stone on each side measures 5.35m.

Donggung Palace and Wolji Pond

According to the historical records of Samguk-sagi, Wolji Pond was built during the 14th year of King Munmu (r. 661-681 AD) of the Silla Kingdom (57 BC-935 AD). Small mountains were created inside the palace walls, beautiful flowers were planted, and rare animals were brought in to create an exquisitely exotic garden fit for royalty. The pond was originally built in Wolseung Fortress (built in 101 AD during the Silla period), but the fortress was destroyed and now lies in ruins. In 1974, an excavation project revealed large spherical shapes (measuring 200 meters in diameter and 180 meters in height) which indicated that 3 islands had been located in the pond. Thanks to these important findings and existing historical records, Wolji Pond has been restored to nearly its former glory.