Forrest, John (b. 1847), was an explorer of Western Australia. He belonged to the Survey Department, and in 1869 set out from Perth in a N.E. direction, and reached long. 123° E., lat. 29° S. through a barren country of salt marsh and bush. In 1870 he surveyed along the S. coast, and in 1874 along the E. He has also surveyed much of Western Australia.