Indonesia–Malaysia border crossings. Illegal immigrants are also known to use such crossings. There are numerous scheduled sea crossings between Indonesia and Malaysia, mostly between ports in the former's island of Sumatra and Peninsula Malaysia. Here is a list of ports (Indonesian port followed by the Malaysian port) where scheduled boat services operate as of April 2008: Sumatra-Peninsula Malaysia North Kalimantan-Sabah Indonesia–Malaysia border The border between the Southeast Asian countries of Indonesia and Malaysia consist of both a land border separating the two countries' territories on the island of Borneo as well as maritime boundaries along the length of the Straits of Malacca,
Malaysia area of . It has land borders with Thailand in West Malaysia, and Indonesia and Brunei in East Malaysia. It is linked to Singapore by a narrow causeway and a bridge. The country also has maritime boundaries with Vietnam and the Philippines. The land borders are defined in large part by geological features such as the Perlis River, the Golok River and the Pagalayan Canal, whilst some of the maritime boundaries are the subject of ongoing contention. Brunei forms what is almost an enclave in Malaysia, with the state of Sarawak dividing it into two parts. Malaysia is the only