Nyamal Country takes in most of the De Grey River Catchment, other than its headwaters wuluyu (south) in Palyku and Nyiyaparli Country, and about 65km wartalpa (north), going to the sea in Ngarla Country. The major tributaries across Nyamal Country include the Oakover, Nullagine, Coongan, Strelley, Shaw and Turner Rivers. Nyamal Country is bounded at the east by Jingkarn (the Gregory Range) beyond which are the sand dunes of the Great Sandy Desert.
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