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 confrontation an abject failure, the poorly trained and equipped forces were unable to seize key objectives such as capturing the Sultan of Brunei, seize the Brunei oil fields, or take European hostages. Within hours of the insurrection being launched, British forces based in Singapore were being mobilised for a prompt response. The failure of the insurrection was clear within 30 hours when Gurkha troops airlifted from Singapore secured Brunei town and ensured the Sultan's safety. The degree of Indonesian support for the TNKU remains a subject of debate. While Indonesia at the time denied direct involvement, it did sympathise with the