East Malaysia is 50% bigger than Peninsular Malaysia at , comparable with South Dakota or Great Britain. East Malaysia contains the five highest mountains in Malaysia, the highest being Mount Kinabalu at 4095 m, which is also the highest mountain in Borneo and the 10th highest mountain peak in Southeast Asia. It also contains the two longest rivers in Malaysia – Rajang River and Kinabatangan River. Banggi Island in Sabah and Bruit Island in Sarawak are the two largest islands that are located entirely within Malaysia. The largest island is Borneo, which is shared with Indonesia and Brunei. The second largest island
Indonesia–Malaysia border the assertion that the islands belonged to Malaysia and both countries brought the dispute to the International Court of Justice. In 2002, the court decided that the sovereignty of the two islands belonged to Malaysia. The court however did not determine the maritime boundary in the surrounding waters and specifically decided that the 4° 10' North parallel which marked the easternmost portion of the Indonesia-Malaysia land border in Sebatik island did not extend to sea to form either the territorial sea or continental shelf border. The birth of the Indonesia–Malaysia border, or at least the portion for what is today