Vault symbols are collectible items in Borderlands 4. These collectibles are necessary for area completion, but if you are just a fan of gear and story progression than you might skip these optional symbols. However, for completions, everything matters, and you do get XP and some extra lore on each Vault Symbol location in Borderlands 4.
Out of all 46 vault symbols 3 are located in Coastal Bonescape.

Coastal Bonescape Vault Symbol Locations in Borderlands 4
Location #1
The first vault symbol is near the Coast of Bonescape. I took the image from where I was standing at that point. You can be anywhere else on the map at the start. First look for the vault symbol on the map, if it’s not visible to you try zooming in to the map to get the vault marker on screen.

Go to a wooden house and climb up to its wooden hut roof as marked in the image below.

Once you have reached at the top, you will see two platforms climb on the second one, and you will see a vault symbol hidden at its back on wall

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Location #2
The second and third vault symbols are quite close to each other but on the other, or I can say the opposite side from where you located the first vault symbol. For reference the ma location of 2nd and 3rd vault symbol is attached below.

Next from the existing point there will be a house with windmill attached to it. Clear the area before looking for the vault symbol, or you can just avoid them by quickly running inside the windmill building. To enter it go from the broken wall on your left after crossing the bridge.


Go to the first floor by using stairs and at the start of first floor the 2nd vault symbol is behind the wall.

Location #3
The last vault symbol is on the wall of the mountain wall. Go up from the stairs and go out from the roof to your left open in the area.

From that open area see to your left and walk past a house that is in front of you. The last vault symbol in Borderlands 4 in coastal Bonescape will be to your right on the mountain wall.

Apart from these three you can find more at Fortress Indomita.