Minmi is an outer western suburb of Newcastle, New South Wales, Australia, located 19 kilometres (12 mi) from Newcastle's central business district. It is part of the City of Newcastle local government area. Minmi was an important coal mining centre in the second half of the nineteenth century, particularly under the ownership and management of J & A Brown. Minmi's mines were connected by a private railway line across the Hexham Swamp to J & A Brown's loading facilities on the Hunter River at Hexham. J & A Brown's engineering workshops were also located at Hexham.