Mammoth Cave, a 15-minute drive south of Margaret River, is a natural time capsule and home to ancient fossil remains of extinct animals.
Nearby are Lake Cave and Jewel Cave but we chose Mammoth Cave because of its audio self-guiding system, which allows visitors to travel through the fascinating underworld at their own pace.
Directly below CaveWorks lies Lake Cave, a stunning, pristine chamber deep beneath the earth. Inside the cave a tranquil lake reflects delicate formations that take your breath away. Visitors descend a staircase, gazing up at towering karri trees from a primeval lost world, before entering one of the most beautiful caves in Western Australia.
Jewel Cave seems to defy nature and dwarf those who enter its lofty chambers.
This spectacular recess with its intricate decorations and sheer magnitude is home to one of the longest straw stalactites to be found in any tourist cave in the world.
Giant trees mask fascinating underworld
Giant trees, Karri and Marri, dominate the forest around Mammoth Cave. Karri grows through the valley and on the far hillside, while more open forest consists mainly of Marri.
The Marri belongs to a group of trees known as “bloodwoods” because of the resin which oozes from gashes in its rough, fibrous bark.
In the late summer, when little else is in bloom, local vignerons pray for a heavy Marri flowering to entice the birds away from ripening grapes.
Mammoth Stream collects drainage from the swampy low-lying area to the east known as Nindup Plain. It flows westward towards the sea but there meets a limestone barrier known as the Leeuwin Naturaliste Ridge.
Its tannin stained, acid water finds weaknesses in the limestone which is dissolved enabling the stream to flow through the ridge.
The magnificent Mammoth Cave has been formed by this stream and by the later collapse of the surrounding rock.
Karri grows up to 90 metres high. The main belt of karri forest grows from Nannup to Manjimup to the Frankland River, then east to Denmark and Torbay, near Albany.
Karri has a long straight trunk with smooth bark that is shed each year. The outer bark changes colour as it matures, so the trunks are multi-coloured in shades of pink, orange, grey and white. Karri produces white flowers in spring.