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
Borders of Malaysia and southeast of the Malaysian coastline. There is also a dispute involving the alleged incursion into Malaysian territorial waters by land reclamation works by Singapore at the western entrance to the Straits of Johor. Borders of Malaysia The borders of Malaysia include land and maritime borders with Brunei, Indonesia and Thailand and shared maritime boundaries with China, Philippines, Singapore and Vietnam. Malaysia has a total land border length of 3,147.3 km. Malaysia's border with Brunei is 481.3 km in length. Except for its coastline with the South China Sea, Brunei is completely surrounded by Malaysia's state of Sarawak on the