Approach the pillar with the flat ledge at the top. The gauntlet "tells" you that the pillar is movable, so push it between the two columns that are close to the entrance.

Climb on the narrow ledge of either side column and jump to grab the flat ledge of the movable pillar.

Pull up and turn to face the ledge above the entrance. Jump to grab it and pull up. Pick up the Treasure (11/13) and safely make your way back to the ground.