The Pinnacles

The Pinnacles stand on the flank of Gunung Api in Gunung Mulu National Park - a field of limestone blades up to about forty-five metres high, razor-edged and packed close, formed where rainwater dissolved down through fractures in the rock over millions of years leaving the ribs between. Mulu is on the UNESCO list partly for them. Getting there takes three days: a boat and a twelve-kilometre trek to Camp 5, then a climb of about two and a half kilometres that gains twelve hundred metres, on rock, roots and fifteen ladders bolted to the cliff, with a turnaround cut-off enforced by the guides because anyone too slow will not get down before dark. It is consistently described as among the hardest day climbs in Southeast Asia and a proportion of people who start it are turned back. The viewpoint looks across the blades from the side.

What you actually see

• Limestone blades to forty-five metres - dissolved out along fractures over millions of years.
• Fifteen ladders on the cliff - bolted onto the steepest sections of the climb.
• Twelve hundred metres in 2.5 km - the gradient that makes it what it is.
• A UNESCO site - Mulu listed partly for this karst.

When to go

March to October. Three days.

Honest expectations

This is genuinely hard - twelve hundred metres of climb on ladders and rock, with an enforced turnaround time, and people are regularly turned back. A guide is compulsory. Book Mulu and the trek well ahead; places are limited.

Nearby

Mulu's show caves and the bat exodus are at park headquarters.