In 1935, the Kaohsiung to Tianjin Line was divided into two separate lines: the Kaohsiung to Shanghai line, which started in Kaohsiung and stopped in Keelung, Fuzhou and Shanghai, and the Kaohsiung to Tianjin line, which stopped in Keelung and Dalian before arriving in Tianjin. A new island line was also opened between Kaohsiung and Magong, in the Penghu Archipelago (Pescadores). Kaohsiung to Yokohama, Osaka, Haikuo and the Penghus were designated tramp routes. In 1937, at the outbreak of the second Sino-Japanese War, Kaohsiung Harbor became considerably busier due to military needs. Cargo handling volumes surged to 2.5 million tons. The second stage of port development was completed that same year.