Great forest - green and dense. 4-5 hours from Johor bahru / Singapore, Very good nature break with quiet and scenic experience. We followed Singapore-Kluang-Kahag-Peta (park headquarters). Do swimming in blue lake; tube rafting in the river nearby; visit the waterfall nearby the basecamp. Walk to NERC - the library nearby.
Commonly spotted: few types of Monkeys,giant squirrels, flying squirrel, monitor lizard, snakes; Difficult to spot big animals (as expected); numerous flowers, butterflies and birds and colorful insects. One of the most amazing experience was to see a butterfly falling for flower-like praying mantis. Couple of types of woodpeckers, plenty of sunbirds, an eagle, bee-eaters, paraquets, few types of robins, bats, and others
If you are an experienced hiker / jungle trekker, this may be easy place for you. You may opt for hiking in the deep forest, They have a few options. Good for enthusiastic nature lovers, hikers etc. Leeches are plenty: Those who freak out by leeches, its hell. For others, some simple remedies like Dettol / Axe oil works. The staff / guides are very friendly but English is problem. They are mostly from Orang Asli village. Surely avoid rainy season - Dec, Jan etc.