The brigands hiding in the Brown Lands are responsible for looting the relics of Parth Celebrant and bringing them to their hideaway.
'The brigands of the Brown Lands are a thieving lot, as you well know, looting the relics of the Field of Celebrant and bringing them here to stockpile.
'Would you go to Helstor and see if you can find the treasure stores of the brigands? It will likely be in a cave at the back of the camp.'
Treasure-stores can be found in a cave within Helstor, north of Etheburg.
Céola asked you to go to recover the stolen treasures from the brigands of the Brown Lands.
Céola is at Etheburg in the Brown Lands, south of Helstor.
You should bring the recovered relics to Céola.