The Cape Range karst consists mainly of three types of limestone. The uppermost, and thinnest layer, the white Trealla Limestone, is mosty dissolved and eroded away. Some significant patches occur on the flanks of the range and it does contain some small caves. It is a hard, crystalline limestone tending to fracture into sharp shards and caves in this limestone are small and difficult.
The layer below is Tulki Limestone. This is the layer that will most interest cavers as it is the main cave-bearing limestone. Again, it is a hard crystalline limestone that shades from white in the uppermost layers to pinkish in the lower regions. It varies from about 50 to 100 metres thick. The caves in this limestone are mainly vertical shafts, occasionally with crawlway sized and, less occasionally, with walking dimension tunnels leading off for generally short distances. There are a few exceptions to this rule. Wanderers Delight has been surveyed to nearly 7 kilometres length along a multi-level and multi-branching network of crawlway passages. Chambers of standing height and higher give regular relief to sore necks and knees. Good knee and elbow pads are a must for serious explorers in the Capes caves. Many tiny leads remain to be explored in Wanderers Delight but these are season-dependent due to long-term standing water pools. The remaining leads are many but are also very small and difficult.
Some of the caves require a degree of technical expertise in vertical techniques although many are simple shafts consisting of a single pitch. Conversely, some of the caves require several pitches to be negotiated and as most of the caves are in the national park, there are virtually no fixed artificial anchors and all caves must be negotiated via temporary rigging, eg tape and cord slings, tricams etc.
The third main layer of limestone is the Mandu Calcarenite. This limestone can be seen in the lower regions of the gorges, particulary along Shothole Canyon, where high exposures of it are easily accessed from the nearby road. It is a whitish, chalky and relatively soft limestone.
A keen eye will easily spot fossils of shells and echinoids in all the limestones.
In the deeper caves the temperatures are generally up around the 27°-29° C mark. If wearing knee and elbow pads, it is generally more comfortable to explore in shorts and t-shirt. The temperature, coupled with the high humidity, makes the cave environment a taxing, tropical adventure and caving in overalls could potentially assist in causing heat exhaustion. Frequent rest breaks and cool water are recommended on the longer trips. If overalls are preferred then the lightweight version are all that is required.
Many areas of the range have had little visitation and there is always a very good chance that keen walkers will find new, unexplored features. When walking in the ranges, the locals generally wear shorts coupled with sturdy canvas gaiters. Gaiters, useful not only for protection from the fangs of venomous snakes, are wonderful for warding off the spikes of the ever-present spinifex. This spiky grass can be a real torment to tender legs.
The caves are rightly famous for their wonderful and varied array of troglofauna and stygofauna. They can be observed in the deeper caves where the humidity and temperature are fairly constant, and in some of the caves that contain water. Schizomids, millipedes, crickets, spiders, fish, eels, all blind, are commonly spotted during cave visitation.
There are many rock-shelter type caves on the western flank of the Cape Range. Many of these were used by the Jinigudira, the original indigenous inhabitants. A cave in Mandu Mandu Gorge returned a date of approximately 34,000 years BP and furnished 22 shell beads and many hundreds of stone artifacts.
