The eight bottles can be found in the following locations:
- As soon as you wash up on the island, on the right side of the beach.
- To the left of the entrance to Souldeep Fasting.
- At the bottom of the ramp leading to Tidal Pools. You need to jump from the platform the gallows are on in Cape Solace to reach this area.
- In the "middle finger" of the northern shore of Scuttle Beach.
- Directly across the river from Aubrey Gilcrest.
- In the "outdoor" section of Mudhold Fasting, where the woman for the side-quest is located.
- In the "outdoor" section of Undersea Fasting, the very farthest point of the dungeon.
- Just outside the entrance to Brigand's Hideaway. You must start the side-quest "The Exiles" after completing the main quest to access this area.
The bottles do not show up on your map (unless you have the Dowsing Rod pre-order item), nor do they have any type of "glow" like normal lootable objects. The achievement will unlock as soon as you hit to take the eighth bottle.