Indonesia–Timor-Leste border

The Indonesia–Timor-Leste border is the international border between Timor-Leste and Indonesia. The border consists of two non-contiguous sections totalling 253 km (157 mi) in length, the larger section of which divides the island of Timor in two. The demarcation of the border between Indonesia and Timor-Leste has been fought over by various parties for 350 years. The first attempts to define it precisely were made by the colonial powers of the Netherlands and Portugal with the Treaty of Lisbon in 1859, but it was not until the Permanent Court of Arbitration's award of 25 June 1914 that the final land border between them on the island of Timor was established. It largely coincides with today's border between the state of Timor-Leste (East Timor), which only gained its final independence in 2002, and West Timor, which belongs to Indonesia, but was still disputed on some points until 2019.