 Some of the infrastructure of the Horonai Railway remains in use today, as the Temiya Line and Muroran Main Line, connecting Minami-Otaru Station and Iwamizawa Station; these began operations in the 1880s.The Hokkaidō Colonization Office was established in 1869, as the new Meiji government sought to take advantage of the natural resources of the island.The American engineer Horace Capron, invited to Hokkaidō by the government for this purpose, determined the presence of a sizable coal deposit in the upper reaches of the Horonai River.