Guide:
Northwestern Cyrodiil, northwest of Fort Aleswell.
Collectible at this location is inside Underpall Cave – public dungeon. Outside of Underpall Cave is protected by Bloodborn Minions camp. Next to the tents in camp you can notice a small wooden path that leads toward Underpall Cave and couple of metal cages.
This is one of the public dungeons where it is easier to collect a Skyshard. It is in the largest cave room, just straight ahead from where you enter. A few Bloodborn Minions that patrol this area should not pose any threat. It is on top of a small wooden platform. There are many metal cages that surround it. Try not to fall down off of the platform. Dark depths that also hide the angry embrace of a Bone Colossus are not for everyone.