Kopuaranga railway station was a flag station that served the small rural settlement of Kōpuaranga, 12½ km north of Masterton, in the Wairarapa region of New Zealand’s North Island. It was located on the Wairarapa Line between the stations of Opaki and Mauriceville. From its opening in 1886 it handled both passenger and freight traffic for 97 years until closure in 1983.

Masterton is a large town in the Greater Wellington Region of New Zealand that operates as the seat of the Masterton District. It is the largest town in the Wairarapa, a region separated from Wellington by the Remutaka ranges. It stands on the Waipoua stream between the Ruamāhunga and Waingawa Rivers – 100 kilometres north-east of Wellington and 39.4 kilometres south of Eketāhuna.