The Farmer's Treasure Genshin Impact world quest involves freeing Saimon Jirou from his cage on Jinren Island (use a key found in the tree across from the cage). Saimon Jirou will ask you to collect the Old Stone Slates from around Narukami Island, Inazuma.
The Farmer's Treasure will not appear in your Journal until all four Old Stone Slates have been obtained. These Old Stone Slates can be collected in any order.
Old Stone Slate Locations
Related: Sakura Aborism: all tree locations in Genshin Impact
Old Stone Slate #1
Progress the Sacred Sakura Cleansing Ritual quest by cutting a deal with the Konda Village Chief and exploring the bottom of the Konda well. After solving the well puzzle, you'll gain access to a room with various treasures and an Old Stone Slate.
Old Stone Slate #2
Defeat the Nobushi samurai enemies at this camp to collect the second Old Stone Slate.
Old Stone Slate #3
Find the third Old Stone Slate in the Araumi ruins. You'll need to progress Sacred Sakura Cleansing Ritual to the Cleansing Defilement objective, and solve two cube puzzles.
Old Stone Slate #4
After collecting Old Stone Slate #3, keep exploring the ruins. #4 is located further inside in a large cavern.
Read about Inazuma and upcoming events in The Immovable God and the Eternal Euthymia: Genshin Impact 2.0 Patch Notes. We've also got you covered on the next Genshin Impact banner and codes to redeem for in-game freebies!