Cheomseongdae is the oldest building I've seen

Cheomseongdae is the oldest astronomical observatory in East Asia, and Korean National Treasure # 31, located in the city of Gyeongju, ancient capital of the Silla Kingdom which reigned for nearly 1,000 years. I went to South Korea on vacation in 1996. We spent about a week in the capital, Seoul. Then we travelled all …