The inlet is situated 65 kilometres (40 mi) west of Esperance in Stokes National Park and is set is a large river valley with permanent deep water and high dunes located on either side.

Stokes Inlet was named in 1848 by John Septimus Roe, the Surveyor General of Western Australia, while leading a five-man exploration expedition along the coast, commemorating John Lort Stokes' work on HMS Beagle, surveying the Western Australian coast.

[4] The mouth of the river is in the middle of Dunster Castle Bay; it is closed by a sandbar that cuts the estuary off from the sea and only opens every few years.

[5] The aquatic flora of the estuary are dominated by the small green algae Polyphysa peniculus, the stonewort Lamprothamnium papulosum, and the seagrass Ruppia megacarpa.

[6] Marine species flourish at times when the bar is open; blue manna crabs, juvenile prawns, cockles and mussels have all been identified in the inlet.