South Korea’s Ministry of Unification on Monday announced plans to resume the inter-Korean project of conducting an archaeological excavation of Manwoldae Palace in the North Korean border city of Kaesong.

Manwoldae – a Koryo-era royal palace built in the 10th century – is considered one of the most important historical sites in the country, but has been inaccessible to South Korean archaeologists and historians since it is located in Kaesong, north of the demilitarized zone separating North and South Korea.

South Korea’s Office of the Association of Inter-Korean Historians sent an advance team of 13 historians to Kaesong on Tuesday