The Ulu Temburong National Park is located in the remote part of the Batu Apoi Forest Reserve. The park covers 550 square kilometers of unspoiled rainforest, the vast majority of which is set off for protection, so visitors are allowed to visit only a small piece. Thanks to Brunei's successful forest protection program, the rainforest in the park has never been deforested. There are no roads, so access is only by long boat. Highlight of the Ulu Temburong National Park is the Canopy Walkway, which stands 50m tall while set on a treetop. Visitors are only allowed to enter the park on guided tours, which you should reserve in advance as they fill up, especially in the high season. Tours generally leave from Bandar Seri Begawan. More expensive than Malaysia's national parks, but one of the most popular attractions in Brunei.