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NSW is blessed with an amazing number of canyons, that is, narrow cuttings through rocks formed by running water. Around Sydney, canyons are typically ‘slot’ canyons. Slot canyons are surrounded by high walls of rock, and limited light reaches the water in the bottom.
Canyoning is the activity of following a watercourse through a canyon. It usually involves bushwalking to an upper section of the watercourse, following the water for a while, then exiting via a bushwalking route at the bottom. Often, canyoning involves scrambling, swimming, abseiling, jumping, balancing, climbing and anything else required to travel downstream. Some canyons have well-worn tracks to get in; others are accessed purely by off-track navigation.
Canyoning is a fun activity but requires a significant amount of technical knowledge and skills.