About 50km west of Kotamobagu, this very rarely visited 2871-sq-km national park has the highest conservation value in North Sulawesi, but it’s pretty inaccessible. The park (formerly known as Dumoga-Bone) is at the headwaters of Sungai Dumoga (Dumoga River) and is a haven for rare flora and fauna. The maleo bird, a large megapode, is found in large numbers here (more than 3000 were released into the park in 2012). Other wildlife include the yaki (black-crested macaque) and a species of giant fruit bat only discovered in the 1990s.
Beyond the flora and fauna, there are several poorly understood archaeological sites near Toraut consisting of multiple large rooms carved into the sides of cliffs, presumably for burials. These sites are no longer used and are still hidden in the forest, lending your trek there a profound sense of adventure and discovery.