The Nakdong River or Nakdonggang is the longest river in South Korea, which passes through the major cities of Daegu and Busan. It takes its name from its role as the eastern border of the Gaya confederacy during Korea's Three Kingdoms Era.

Silla, was a Korean kingdom that existed between 57 BCE – 935 CE and located on the southern and central parts of the Korean Peninsula. Silla, along with Baekje and Goguryeo, formed the Three Kingdoms of Korea. Silla had the lowest population of approximately 850,000 people, which was significantly smaller than those of Baekje and Goguryeo.