The division of a river into a stable multi-channel system with levées, backswamps, and large, stable islands. An anastomosing channel, unlike an anabranching channel, has distributaries of its own. Valley incision starts at outflow points; up-valley incision begins where the flow rejoins the main channel (Schumm et al. (1996) GSA Bull. 108). In time, the channel segments join, making a new anabranch of the anastomosing-channel system; see Kleinhans (2012) ESPL 37, 12, 1337. Many anastomosed systems cannot be categorized; one common factor seems to be low specific stream powers, thus explaining the river’s inability to maintain channel capacity via sediment transport and erosion; see Makaske (1998) Earth Sci. Rev. 53.