Canyoning involves walking, scrambling, abseiling and swimming down deep gorges sliced through rock over millions of years. They can take many forms. The Blue Mountains and Wollemi are home to hundreds of deep, dark, narrow sandstone slot canyons, at times so tight you can barely squeeze through. Further south Kanangra offers more open canyons that are also much deeper, plunging nearly a thousand metres through broken metamorphosed quartz. Bungonia, famous for its caves, houses similar deep open gorges, but here cut through jagged, cave-filled limestone. Internationally, stunning canyons can be found on every continent, formed in different rocks in as environments as diverse as European mountains, Asian rain forests, and even Middle Eastern deserts.

While every canyon is different, most in the Blue Mountains are narrow, dark places with moss covered walls and swirling walls produced by relentless scouring with water. Still others can be deep and straight, formed along fissures or weaknesses in the rock. In some, rock collapses have created dark, cave-like tunnels illuminated with glowworms.

Canyoning around Sydney, like bushwalking, has a rich history, with almost all of the most known canyons first explored in the last fifty years. In more remote areas new canyons are still being discovered; places kept secret for eons by their remoteness, ruggedness and concealment in bush labyrinths.

Despite their age, and remoteness, canyons are fragile places, with carefully balanced ecosystems, unique plants and animals, and fragile soils. Damage is easily caused, not only harming the environment, but diminishing the experience of future visitors. People who enter them should adhere strictly to the canyoners code of ethics. Keep parties small, never bolt rocks, don’t place cairns, pack out all your own rubbish (and any other filth you find) and try and leave these special places pristine for future generations.

Despite their fragility, canyons can be deadly. Barely a year goes by without them claiming a life. Never enter without the appropriate skills and equipment. Know how to navigate. Be prepared for the worst.