"Kenyan-Kayan-Kajang" is a term referring to a complex of riverine culture groups living in Sarawak. The Kenyah and Kayan are the main groups, whereas the Kajang consist of a number of small groups that are assimilating to one or the other of the other two. There are numerous subgroups as well. The Kayan live in the central portions of major central Borneo rivers (Kayan, Mahakam, Kapuas, Rajang, and Baram); the Kenyah live in the Apo Kayan drainage. The complex as a whole occupies an area within 1° to 3° N., and 113°00′ to 116°30′ E. In 1980, the population of Kenyah and Kayan was 28,925. Kenyah and Kayan are closely related Austronesian languages.