A climbing trip became a scramble for survival after a falling rock left one man injured in NSW.

The 61-year-old climber was 150m high on Crater Bluff when he was struck in the head, in the Warrumbungles National Park, about four-and-a-half hours northwest of the Blue Mountains about 1pm on Saturday.

He was left with cuts and a suspected concussion.

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The injured man and his climbing partner were on a section of the climb called Cornerstone Rib, where they managed to reach a ledge to rest on.

That is where they activated an Emergency Position Indicating Radio Beacon (EPIRB), NSW Police said.

Eleven hours later, the climbers — believed to be from Victoria — were winched to the top of Crater Bluff and treated.

PolAir and two critical care paramedics were sent out as part of the multi-agency emergency operation.

They had to remain “in-situ” overnight, before both rescuers and climbers were winched out of the national park at 8am on Sunday, police said.

The 61-year-old climber was taken to Coonabarabran Hospital with minor injuries.