Cossack (Historic name : Tsien Tsin) is an historic ghost town located 1,480 km north of Perth and 15 km from Roebourne in the Pilbara region of Western Australia. The nearest town to Cossack is Wickham.
Cossack is located on Butchers Inlet at the mouth of the Harding River. It is reached by a single, sealed road that follows the original causeway across a series of tidal salt flats. The overall landform of the region around Cossack is a low, flat plain with occasional rocky hills and ranges. The vegetation is mainly grass, spinifex and low shrub, with occasional trees (mangroves) along watercourses and in gullies. The mangrove scrub becomes quite dense along the shoreline and at the mouth of the inlet.
The main road from Roebourne to Cossack continues past the town of Wickham and the Cape Lambert iron ore port (operated by Pilbara Iron), and terminates at the fishing town of Point Samson. The townsite is not visible from the main road, and only becomes apparent as the road rounds Nanny Goat Hill.
The site of the former town is defined by Nanny Goat Hill, Tien Tsin Lookout, the hilly ground to the north-east and north-west, and Butchers Inlet to the east and south-east. Past the townsite, the road winds up to the Reader Head Lookout, from which sweeping views of the surrounding coastline can be seen. Many of the buildings are listed by the National Trust.
The erstwhile Tien Tsin Harbour is now known as Port Walcott