When you play Horizon: Zero Dawn, getting to the Cauldron doors can be pretty straightforward as you just see the map with triangles. Getting to Cauldron Zeta however is harder.
When you reach your destination, you will see that the entrance door is locked and nothing opens. You may also encounter lots of Sawtooth guarding the area. It can be pretty annoying if you don’t know what to do.
Don’t fear because there is a hidden passage that takes you inside the Cauldron. You want to look at the left side and climb into a cliffside. You’ll know what it is when you see a Watcher guarding the area. Also, see screenshot below for what it looks like.
When you climb this cliffside, there should be a type of cave that you can walk inside of. After you do that, you should press and hold triangle to override the door. Once you do that, you have gained access to Cauldron Zeta! Accessing Cauldrons are important in Horizon: Zero Dawn because they allow you to override the machines.
