One of the best activities to do in Sabah, Malaysia is to visit Mount Kinabalu. This mountain is the highest peak in Southeast Asia, standing at 4,095 meters tall. The mountain is located in Kinabalu Park, which is a UNESCO World Heritage Site. Visitors can hike to the summit, which typically takes 2 days, or take a guided tour to the base camp. The park also offers other activities such as rock climbing, bird watching, and nature walks. Another popular activity in Sabah is to visit the Sepilok Orangutan Rehabilitation Centre, where visitors can see orphaned orangutans being rehabilitated before they are released back into the wild.