Quest line starts at Martha Kiyen in Northern Wheat Plantation. Requires 100 amity.

you can now get the knowledge from NPC, questline is gone

Talk to this Guard. Also make sure to grab the knowledge from the Explorer in front of him. They are at the entrance of Bree Tree Ruins Cave.

Since the location isn't mentioned anywhere, they're located west of the Bree Tree Ruins.
The Knight has the knowledge for Bree Tree Forest Cave and the Explorer has the knowledge for Shards of Ancient Architecture.

- Map Location
- Area Location - (same image as GrimElite).