The Excavation skill-line is part of the "World" category in the Elder Scrolls Online and is used for the Antiquities System. The Excavation skill-line lets you excavate treasures from the Antiquities System.

Another neat feature about the Excavation skill-line is that it offers the "Keen Eye: Treasure Chests", which makes it easier to see all treasure chests in the game.

To unlock the Excavation skill-line you have to visit the city of Solitude in Western Skyrim, to do that you will have to own Greymoor. Once you are inside the city, head towards the marked building (Antiquarian Circle) in the picture below. You will find a NPC called Verita Numida inside, talk to her to begin your journey!

A more detailed walkthrough on how to unlock the Excavation skill-line can be found in the Antiquities System Guide.

To level up the Excavation skill-line in the Elder Scrolls Online you have to complete leads and achievements related to excavation. You can learn more about how to level up the Excavation skill-line in the complete Antiquities Level 1 - 10 Grind Guide.