If you are looking to participate in Destiny 2’s newest activity – the Menagerie – then you’ll need to earn some runes and Imperials. Tied to Weekly Bounties offered by Werner on Nessus, completing these will give you a treasure map. One of these maps will ask you to find a treasure chest in the Spine Burrows. Finding this can be a bit tricky, especially if you aren’t used to exploring Io’s caves.
To find the Spine Burrows treasure chest, land at the Lost Oasis beacon. From here, open up your sparrow and drive to the other side of the massive tree. Climb up the plateaus until you reach one with a small cave entrance and a still pool of water. Enter the cave here and follow the path until you reach the Spine Burrows area.
Now kill all of the enemies residing inside before hopping down into the middle of the room. You will see the chest embedded in some rocks under a raised platform. It emits a glowing blue aura so it shouldn’t be that difficult to spot. Now just open it to earn some Imperials, a piece of Powerful Gear, and a rune.