Ōfunakoshi-Seto and Manzeki-Seto, the two canals built in 1671 and 1900 respectively, connect the deep indentation of Asō Bay (浅茅湾) to the east side of the island.
Ōfunakoshi-Seto e Manzeki-Seto, as dúas canles construídos en 1671 e 1900 respectivamente, conectan a profunda hendidura de Asō Bay á beira leste da illa.