Man's leg trapped under boulder in Macquarie Pass National Park

NSW Ambulance paramedics, Lake Illawarra Police, Rural Fire Service brigades and multiple units from the SES were involved in the rescue effort on the Clover Hill Trail in the Macquarie Pass National Park.

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The initial call for help came in about 11.45am, with reports the 21-year-old hiker fell down a gorge and became wedged against a boulder.

It's understood the giant rock could have weighed up to 1.8 tonnes.

"Some areas of the national park are challenging when it comes to radio communication and this equipment goes a long way in making communication easier for all agencies on the ground," posted the SES Shellharbour Unit to Facebook, who were assisting with communications support.

The Clover Hill trail is a 3km walk each way from the emergency crews' staging area in the car park to the gorge, and further along the cascading creeks.

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"About 6.45pm, the man was freed and extracted from the gorge before being airlifted to St George Hospital with serious leg injuries," a NSW Police spokeperson told the Mercury.

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