The Medway River is a tributary of the Awatere, flowing into the Awatere from the south, about 20km south-west of Seddon. The river flows through a region of uplifted marine sediment, with fossils frequently being exposed in the soft mudstone. The surrounding area is used for agriculture, but near the river there are significant patches of manuka and other native scrub, At the head of the valley is a private tramping track, the Awatere Tussock Track.