Archives are a new addition to Assassin's Creed Odyssey: Judgment of Atlantis. They are locations where you can find many items giving you knowledge of Isu. Thanks to them, you will quickly develop your character.
Archive of Hephaistos is located in the southern part of Oikos of Atlantis.
The entrance to the archive is at the bottom of the building. You can notice it easily because the door glows golden.
You can see the first codex immediately after entering the location.
A torch is standing in the center. Destroy it to weaken opponents.
On the right, you will find a codex and a chest with knowledge. To get there, you need to climb the stairs or walk on a rope.
The captain is hiding at the bottom of the location. If you don't lure him out by making a lot of noise during fights, he will be waiting for you there. You can notice him fast - he is standing in front of a fireplace.