Ice Palace

For The Legend of Zelda: A Link to the Past on the Super Nintendo (SNES).

Entrance: Ice Lake (Dark World)

Pits

In 3 rooms here (B2, B4, B5), a pit takes one heart from Link in every mail and puts him back at the spot where he came into the room. Pits in the other rooms drop him to the floor below without hurting him.

Spikes

Spike blocks are in 3 rooms here (B2, B3, B4). Walking into one takes one heart in every mail and throws Link back. The Magic Cape keeps them from hurting him.

Spike floors are in one room here (B3). Standing on one takes one heart in every mail. The Magic Cape and the ring of the Cane Of Byrna keep it from hurting Link.

From the official guides

The Ice Palace is inside a huge iceberg floating on a lake in the Dark World.

ファミコン通信編集部責任編集ゼルダの伝説神々のトライフォースのすべてがわかる本 (アスキー, 1992), p. 55, translated by 101Leafy

No single floor of the Ice Palace is very big. But the links between floors are quite complex, and you cannot clear it unless you keep track of which room lies under the one you are in.

ファミコン通信編集部責任編集ゼルダの伝説神々のトライフォースのすべてがわかる本 (アスキー, 1992), p. 56, translated by 101Leafy