Deer Cave

Deer Cave sits inside Gunung Mulu National Park and ranks among the largest natural cave passages on Earth. The entrance spans 174 meters in width and reaches 120 meters in height, enough to let a Boeing 747 pass through comfortably.

The British Borneo Geological Survey documented this formation in 1961, opening the door for further research. Later expeditions mapped miles of passages and prepared the site for visitors over the following decades.

Local Penan and Berawan communities still call this formation Gua Payau, a name tied to their knowledge of the rainforest and its shelters. Their paths and stories helped scientists navigate the inner sections when mapping began decades ago.

A three-kilometer plank walkway winds through the rainforest to reach the entrance, so wear sturdy shoes. Bring your own flashlight, since the interior relies on limited artificial lighting.

Around three million bats leave the formation each evening in spiraling swarms that form dark clouds across the sky. A camera system installed in 2008 records their flight patterns and supplies researchers with data on behavior and population shifts.

Location: Gunung Mulu National Park

GPS coordinates: 4.13194,114.91889

Latest update: December 5, 2025 22:28