Kemabu River: Papua’s High-Altitude River with a Mind-Bending Visual Illusion

Hidden within the Carstensz Pyramid trekking corridor lies the Kemabu River, one of Papua’s most fascinating natural surprises. Sitting at roughly 3,000 meters above sea level, it is known as the highest river in the entire Carstensz region. But what makes it truly unforgettable is the way the water seems to flow uphill.

Many trekkers, on their first encounter, stop in disbelief. From certain angles, the river’s current appears to move toward higher ground, as if climbing upward instead of following gravity downward like any normal river. It is a moment that often leaves people speechless, staring and asking the same question: “Is the water really flowing up?”

Until today, there has been no scientific study to officially explain the phenomenon. However, most experienced guides and climbers believe it is a visual illusion created by the terrain. The slopes, curves of the valley, and the perspective from the trekking trail can trick the eyes, making the water’s natural flow look reversed. In reality, the river behaves as any river would, but the landscape plays a clever trick on anyone passing through.

Even if it is “just an illusion,” the Kemabu River remains one of the most memorable sights on the Carstensz route. Its high-altitude location, combined with misty hills and untouched scenery, makes the entire experience feel surreal. Trekkers often spend a moment sitting near the water, simply appreciating how nature can still surprise us in ways we don’t expect.

The Kemabu River may not actually flow upward, but the illusion it creates is enough to spark curiosity and storytelling among adventurers. In a place as remote and wild as Carstensz, even a simple river can feel magical.