Borderlands 2 is filled to the brim with quests, and one in particular—aptly titled “The Lost Treasure”—is a bit harder to solve than most. The quest comes in several parts, and involves some situational awareness and familiarity of the Caustic Caverns, which open up after *spoiler* Sanctuary is lifted into the air.
There’s a good chance that you’ll be doing this quest a short while after you’ve already been to the Caustic Caverns, but in case you’ve managed to acquire the quest beforehand, know that you’ll have to head on over to the Sanctuary Hole to get to the former location.
To start the quest off, head to Sawtooth Cauldron. Once there, to to the precipice just ahead of where you spawn, jump down and head up the trail on the right, as you see below:
The box adjacent to the pair of panties on the chair starts the quest. Having already done the quest, you won't see it lit up in my screenshot. There's an ECHO in the box. It goes without saying that the bandit who hid it there's a bit of a pervert, but don't worry: the bandit treasure isn't more pictures of Moxxi.
Now that you've started the quest. Just head on to the area below and kill all the bandits until you get four maps. It's best to do the quest while you're here on other errands, so you don't waste your time by just wasting bandits—not that there's anything wrong with that.
Brick will give you a backstory about the treasure, which was hidden down in the Caustic Caverns by remnants of the Crimson Legion. It’s interesting stuff, if you care about the Borderlands lore (and you should).
Once you’ve found the maps, you’ll begin the second chain of The Lost Treasure quest so head on to the Caustic Caverns. We’ll follow the clues in the order the game provides for the sake of consistency.
Under the acid-soaked railway
Head to the right after you enter the Caustic Caverns until you find the area with the large yellow Crystalisks by the acid pools. You’ll notice a few large columns supporting derelict rail tracks. Head to the third one out from the cliff and you’ll discover a switch at its base. Hit the switch.
In the warehouse on the shore
Just keep heading north past the acid-soaked railway and follow the shoreline until you come to an area with a ton of Threshers and a large, derelict warehouse with larvae within. Head outside to where the warehouse meets the shore and look for a switch.
In the digger's shadow
When I first did this quest, I misread 'digger' as 'dagger' and kept wondering where some damn dagger was. As it turns out, you're supposed to look for a big mining diggers—specifically the one in the western part of the map. The switch is located inside the semi-enclosed building beneath its shadow.
Within Dahl's bloody sixth
You'll find the last switch within the Dahl Deep Core 06. The location's closed up until you make a full circle of the entire map. It's located to the left of where you enter the map. The room you're in should have a lot of blood on the walls and a long ladder heading up to the surface.
Trigger the final switch and you'll be rewarded with the location of the treasure, which happens to be upon the ramparts above the mining facility. The treasure's just a ways ahead, so I won't spoil you with any more pictures.
Happy hunting!
[This article is part of a series of Borderlands 2 Guides. Be sure to check out our guide on how to get to the Minecraft secret location.
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And here's how to get additional Golden Keys and Veteran Skins.]
