Structure

This page lists generated structures in Minecraft. A generated structure is defined as any structure that is disabled when the "Generate structures" world creation option is turned off. Some structures such as dungeons and desert wells do still generate with this option turned off but are listed on this page due to them having the appearance of a structure as opposed to a natural formation.

The Overworld
The Overworld contains numerous generated structures, at a wide variety of scales.

Buildings
Buildings are naturally generating structures that form above ground. They can contain valuable treasure, but traps and puzzles as well.

Quasi-structures
These structures will generate even when the "Generate structures" world option is disabled, and also cannot be located with the command.

The Nether
The Nether, though equally vast, contains far fewer types of generated structures than the Overworld.

The End
The End is the final and most barren dimension, with no generated structures on its main island. After defeating the ender dragon, gateways to the outer islands are created.

Technical details
Structures are generated for a given chunk after the terrain has been formed. The chunk format includes a tag called that indicates whether structures whose point of origin is in that chunk have been generated. If it is false or missing, they will be generated again. Structure generation is based on what is already in the chunk, so (for example) flagging a chunk that has already been populated for repopulation will approximately double the amount of ore in it.

When structures are generated, they can spill over into neighboring chunks that have been previously generated. Thus, a tree at the edge of the generated world (and probably only visible using external tools) may be overwritten by a lake before the player reaches it. It is also theoretically possible for two worlds generated with the same seed, from the same version of Minecraft, to differ slightly depending on the players' travel routes, because the order in which chunks are generated may determine which of two conflicting structures will overwrite or suppress the other.

Trivia

 * In previous versions, before snow cover was solid, a lava lake with floating snow cover above it could be a deadly trap before the snow melted.