section of the central highlands, east of the Star Mountains, Papua New Guinea, southwestern Pacific Ocean. The rugged range, rising sheer from the south to over 10,000 feet (3,000 metres), is composed of coralline limestone, which is so porous that water falling on it quickly percolates into the ground, making surface water scarce. The highest peak on the range is Mount Wamtakin at 12,001 feet (3,658 metres).