Igloo

Igloos are structures that are naturally generated in snowy biomes. They are small round structures constructed primarily of snow blocks.

Generation
Igloos naturally generate in the snowy tundra and snowy taiga biomes, but not in snowy mountains, ice spikes, snowy taiga hills, or other variants.

Structure
Igloos are composed of snow blocks, sheltering a carpeted interior containing a bed, furnace and crafting table.

In half of all igloos, an oak trapdoor can be found under the carpet (the third white carpet straight ahead from the doorway), leading down a long ladder shaft to a basement. This passageway and the basement are built from stone brick, some of which are infested blocks. In this basement there is a brewing stand, a cauldron, a chest, and beyond the far wall, behind iron bars in two different cages, are a plains/snowy villager and a plains zombie villager. The zombie villager can be cured with a golden apple and a splash potion of weakness, both found inside the igloo. However, this may make the zombie villager lose its profession.

The cauldron is $2/3$ full, and the brewing stand contains a splash potion of Weakness.

Igloos that generate without a basement have a snow block in place of the trapdoor. The villagers, brewing stand, and chest are absent in this case.

One may access the individual structures of an igloo by using structure blocks to manually load them from the /data/minecraft/structures/igloo folder in version.jar. To do so, set a structure block to Load mode, enter igloo/structure name, and press [LOAD]. The individual structures are bottom.

Professions of villagers and zombie villagers
$2/3$, the generated villager is always unemployed, even though there are some job site blocks like brewing stand or cauldron around. However, if the player breaks the iron bars in front of the villager, it finds one of the job site blocks and changes its profession to cleric or leatherworker. The generated zombie villager always has the profession of cleric.

$$, the villager is with a random profession while the zombie villager is unemployed; although it can change its profession to cleric or leatherworker after being cured, due to the presence of the brewing stand and cauldron.

Trivia

 * $$, if a number of items in the igloo furnace are smelted, the light generated melts the igloo window, turning the ice into a water source block. This is intentional.
 * Igloos are internally classified as a temple.
 * The igloo is the first structure to use signs with text on them.
 * As of Village and Pillage, igloos with basements can be easily registered as villages, due to having one villager, a bed, and brewing stands and cauldrons, which count as job sites. However, the villager needs to be freed from the iron bars to claim a job site, or the zombie villager cured and freed, to be able to register as a village. Whether this is a bug or an intentional feature remains unknown.
 * This also means raids can be triggered on the igloo.
 * It is possible for an igloo to generate on a cliff or other incline, causing its secret area to be wholly or partially exposed.