It flows generally northeast to reach a southwestern arm of the Bay of Islands.

[1] Like much of the coast north of Whangārei, the valley is formed of Waipapa greywacke.

[2] The Whangae River Estuary is designated as an area of Outstanding Natural Character, due to its railway causeway (now followed by the Pou Herenga Tai – Twin Coast Cycle Trail) and its tall mangroves (mānawa), which give way up river to saltmarsh.

[3] Bush covers much of the valley, mainly taraire-puriri forest with emergent rimu, rewarewa and occasional totara, pukatea, kahikatea and kauri.

five finger (puahou), mamaku, patē, hangehange, cabbage tree (tī), cutty grass and raupō, with Northland green gecko (kawariki), tomtit (miromiro), brown kiwi, weka, kererū[4] and kōtātā.