Khlong Ohng Ahng, i.e. the southern section of Khlong Khoo Meuang (fig.), a canal dug in 1783, where it connects to the Chao Phraya River (fig.) near Wang Burapha Phirom, to the southeast of and adjacent to Praisanihyakahn (fig.).

It is the second of 3 canals that that semi-circumvent Rattanakosin Island in the east and together with the Chao Phraya River in the west form a three-layered protective barrier, the inner canal being the Old City Moat (map - fig.), the outer one Khlong Phadung Krung Kasem (map - fig.).