The deepest lake on earth, holding a fifth of the world's unfrozen fresh water. Buryat tradition fills it with spirits, and Cape Burkhan on Olkhon is one of the nine shrines of Asia, which not every shaman may approach. A separate body of stories concerns the Baikal mirages, in which non-existent shores and ships are seen above the water; the effect is physically real and comes from temperature layers in the air.