Frost Cave is a room in the Phendrana Drifts area of Metroid Prime. It is a very large cave where visible deposits of what appears to be Phazon line the walls. All of the room's doors are high up, overlooking the frozen lake in the centre. There are many ledges around the edges to access these doors, as well as three stalactites with weak bases hanging from the ceiling. Firing a Missile at each of these causes it to fall, making other doors reachable.
A Glider flying around the room acts as a Grapple Beam point to reach a ledge from which Samus can aim at one of the cave's stalactites. Shooting this one down causes it to land on the frozen lake, breaking the ice and revealing a Missile Expansion below the surface.
- Frost Cave Access (via Purple Door)
- Save Station C (via Purple Door)
- Upper Edge Tunnel (via Purple Door)
- 1 Hunter Metroid (Not in original European and Australian versions.) (First visit) 
- 1 Glider
- Flying Pirates (Later visits)
- Missile Expansion
- With the Grapple Beam, swing from the Glider to the highest point in the room. Once there, look at the ceiling and find a stalactite with a weak spot. Shoot a Missile at it; the stalactite will fall and break the ice.