Archaeologists have made a groundbreaking discovery at the Gaya-ri site in Haman, South Gyeongsang Province, South Korea, believed to be the ancient capital of the Gaya Kingdom. A sophisticated drainage system dating back approximately 1,500 years has been unearthed, connecting the interior and exterior of the fortress.

This is the first time such a drainage system has been found within a Gaya fortress, offering invaluable insights into the engineering and urban planning of this ancient Korean kingdom. The excavation also revealed various artifacts, including pottery, and provided new details about the construction of the fortress walls and the leveling of the ground within the fortress.

The National Research Institute of Cultural Heritage and the National Gaya Cultural Heritage Research Institute announced on November 11 that they had discovered a stone-walled drainage system at the Gaya-ri site, which is believed to have been the capital of the Ara Gaya Kingdom. This drainage system was designed to channel water from the interior of the fortress to the outside. Additionally, the team uncovered new information about the construction process of the fortress walls and the leveling of the ground within the fortress.

Designated as a historic site, the Gaya-ri site has been the subject of extensive archaeological excavations. Previous excavations have uncovered a fortress, numerous buildings, and other structures dating back to the 5th and 6th centuries, the peak period of the Gaya Kingdom. These findings have solidified the site's reputation as the capital of the Ara Gaya Kingdom and a crucial location for understanding the kingdom's rulers and society.

The newly discovered drainage system was found in a depression within the fortress. The stone-walled structure, measuring between 1 and 3.5 meters wide and 16.5 meters in length, was designed to channel water from this depression out of the fortress. The drainage channel widened to a trumpet shape as it exited the fortress, which researchers believe was intended to slow down the flow of water. This type of drainage system is unprecedented in Gaya archaeological sites.

The fortress walls were constructed using the panchuk method, an ancient construction technique involving the layering of earth within a wooden frame. The interior and exterior walls of the fortress were reinforced, and the uneven ground within the fortress was leveled using a technique known as buyeop, which involved layering the ground with organic materials like branches and grass to strengthen the soil. The panchuk walls were 5.5 meters wide, and the combined width of the inner and outer walls and the panchuk walls reached 29.5 meters.

These findings provide valuable new insights into the advanced engineering and urban planning of the ancient Gaya Kingdom. The discovery of the drainage system, along with the detailed information about the construction techniques used to build the fortress, offers a more comprehensive understanding of life in this ancient Korean kingdom.