As the mountainous area is mostly on the eastern part of the peninsula, the most crucial rivers are likely to stream westwards. Two exceptions are classified as the southward-flowing Nakdong River and Seomjin River.

A few on the 토토 commanderies fell or retreated westward within a several decades, though the Lelang Commandery remained like a Centre of cultural and economic Trade with successive Chinese dynasties for four generations. By 313, Goguryeo annexed each of the Chinese commanderies.