Its first regular operations were between Batavia (now Jakarta) - Bandung, and Batavia - Semarang, starting on 1 November 1928. The ceremony was held at Cililitan airport in Batavia (now Halim Perdanakusuma International Airport). The Batavia-Semarang flight was later extended to Surabaya. Gradually, the services were expanded to include other islands in the archipelago, namely to Palembang and Medan in Sumatra, Balikpapan and Tarakan in Kalimantan, and Denpasar in Bali. Immediately before the Pacific War, KNILM also created a network in the eastern part of the East Indies archipelago, serving towns such as Ambon. For this purpose, amphibious aircraft were used, due to the lack of airstrip facilities in the region.