I know that Mt Wilhelm is the highest mountain of PNG but what is the highest on the Island of New Guinea?
Interesting question. The answer is not in PNG.
At 4,884 metres (16,023 ft), Puncak Jaya (sometimes called Mount Carstensz) makes New Guinea the world's fourth highest landmass.
The current population of the island of New Guinea is about 7.1 million people.
What is the highest mountain in PNG?