Abandoned Mines - Crossing the Canyon and Opening the Doors (Part 1)

Scramble up the wooden wall opposite the strongbox.

At the top is an Archivist Map (1/1). This reveals document and mural (or possibly relic) locations, but if you followed this walkthrough you'll already have found them all. Jump across the gap.

Then slide down the zip line and grab onto the crane jutting out over the canyon.

This causes the huge bucket at the top of the zip line to fall.

Climb around to the right...

...then up onto the crane arm.

Now follow the crane arm down to the body of the machine. Turn left, jump across the gap onto the metal catwalk, and then head up the slope and around to the right.