Lava lake

A lake is a small, widespread, naturally-generated terrain feature that contains a volume of fluids (water or lava).

Description
Lakes are shallow and often small bodies of liquid. Water lakes, which are small pools of water source blocks, can generate above sea level or inside caverns. They can also generate isolated underground, connected to no other structures whatsoever. When in a snowy biome, these small lakes are never initially frozen but turn to ice if exposed.

The lakes can also be composed of lava; however, lakes of lava are rare. Lava lakes found at the surface are surrounded by stone (which can be replaced by blobs of blocks such as dirt, gravel and coal ore).

Both types of lakes generate with a small air pocket above them, which may result in floating sand, floating snow cover or even floating trees above the lake. Lava lakes may cause trees to burn away.

Generation
Lakes generate anywhere. Water lakes are most common, generating in almost all Overworld biomes excluding the desert biome and its variants. Lava lakes are rare on the surface but often found in caverns, and replace blocks around them with stone.

Lakes that attempt to spawn in midair are instead lowered down to the highest solid terrain below them. Superflat worlds with them enabled have many more lakes if the top is at a lower level than worlds that are tall.

$$, the air pockets above lakes are generated with cave air instead of normal air. This is true even for lakes that are exposed to the open sky.

Dungeons are able to generate attached to lakes.

Lava lakes
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