Tangkiling Hill is the simplest way to get above the flat river-and-forest landscape around Palangka Raya. The hill rises north of the city near the Rungan River, with forest paths, boulders, shrines, and views back across the surrounding lowland.
It is not a polished national-park experience, and that is part of the point. Come for a half-day walk, preferably early before the heat builds, and bring water and shoes with grip. The outing pairs well with nearby river trips or orangutan-focused conservation visits around the Rungan area.