The main entrance to Cobweb Cave lies some 50 metres above the alluvial plain on the north west flank of Gunong Benarat, approximately 4 kilometres north of Camp Five.

In 1984, when Cobweb was discovered, this area of the mountain had not revealed its caves, unlike north and south Benarat. The major systems of Blue Moonlight Bay / Terikan River in the north and Benarat Caverns in the Melinau Gorge cliffs had been partially explored during the 1978 and 1980 expeditions and had given tantalising insights into the probability that Benarat would be the same as G.Api and G.Buda - riddled with cave passage.

To the first cavers who looked into the entrance it was the striking number of spider webs which instantly gave the system its name. Only later in the exploration, as the survey of the passages revealed a tangle of numerous interlinking loops, did a double meaning creep into the designation.

Inside, a steep, rock-studded slope, twilight lit from the double entrance, leads to the base of a jagged rock island standing in the middle of the entrance chamber. Beyond this chamber anyone entering the cave is pushed this way and that as they try to navigate through huge boulders and the holes between them. However, the caver is consistently led in one direction by the walls of the 30m wide passage, beneath an elegant curved roof. This soon changes as the main north/south routes are met and a multi level maze of passages becomes the norm. At the lowest point are the four sections of river passage separated by short sumps. The waters of the furthest downstream sump are not seen again until they emerge at the upstream sump of the Terikan System ­ 4km away! Within this gap lies the greatest potential for further discoveries under the whole of G.Benarat.

A long and complicated climb up through the levels, gaining a height of 350m above the river, leads to the highest passage in Cobweb. It was to here in 2007 that explorers from Moon Cave made the connection and completed the first through trip. At this level there is now a single passage, some 7km in length, from the Moon Cave entrance in the Melinau Gorge, passing through Cobweb and choking intriguingly above the blank area between Cobweb and the Terikan systems.

The hall-mark of Cobweb is its complicated nature but it also contains some other unique features: in Monolith Chamber, a pure white needle of rock is set upright in a chocolate coloured floor - a natural phenomenon despite its close resemblance to a prehistoric standing stone; <Insert Photo> Deeper into the system, a network of passages called The Rubic Tubes were described by the first to see them as 'beautiful, sand-floored and white-walled passages'.

Yet further into the cave network, The Powder Mountain and The Powder Dome have deep, ancient guano deposits covering the floor, deadening sound and softening the outlines of the passage and fallen boulders. Cavers' tracks in the powder are strong reminders that humans have only recently walked these hidden places, but our impact is stark.

The connection with Moon Cave brought together into one system Cobweb, Moon and Benarat Caverns and we now refer to the whole system as ‘The Benarat Cave System’. The combined length is 50.5km, the second longest cave in the National Park and currently the fiftieth longest cave in the world.

To the north of Cobweb Cave, the Terikan Cave System has been considerably extended over the years and at its most southerly point comes within a few hundred metres of Cobweb's northern reaches; a link here would create a master cave exceeding 90km in total length. Perhaps another connection is waiting to be found, hidden in the depths of the mountain or in the green complexity of the forest?