Cliffside Bunker - From the First Campsite to the Bunker

Stand near the anchor post and fire a rope arrow into the climbing wall on the far side of the inlet.

Same view from a slightly wider angle. In case it's not obvious, that's the Endurance on the far right.

Jump onto the zip line, slide down and press Interact to latch onto the wall with your axe.

The barbed wire on the ledge above prevents you from climbing up here. So move to the upper right side of the rough wall and then jump to the right to grab the horizontal bar.

Climb to the right a bit. Then jump straight up to grab the bar above. Climb along the upper bar around the corner and on to the right as far as you can go.

Ignore the climbable wall below and instead jump to the right and latch onto the larger section of climbing wall.

Climb to the right again and jump to grab the next horizontal bar. Continue climbing around to the right...

...and then up into the bunker.