Rivers are thin, lengthy biomes that frequently generate across the world. They typically serve as a division between two different biomes, but can also split a single biome in two. They are filled with water up to sea level, though rivers may run dry in certain areas due to higher than usual elevation. Exposed grass in rivers takes on a bluish-green hue. Riverbeds consist of dirt, sand, gravel, and clay, and are one of the few places where clay generates, alongside lakes, swamp marshes and ocean hilltops. Seagrass generates atop the riverbed, and sugar cane occasionally generates on the riverbank. Neither passive nor hostile mobs (except drowned) spawn within river biomes themselves, but frequently wander into them from the surrounding biomes if they can spawn there. Drowned can spawn underwater, as can salmon and squid.
When generated between two high-elevation biomes, such as mountains and hills, river biomes may pose a fall damage hazard, but are otherwise mostly harmless.
If this biome is used to generate a buffet world, it appears as a shallow ocean, of no more than 10 blocks deep, with mostly sand, dirt, clay and gravel floor and infrequent grassy islands that rarely contain oak trees and, more rarely, pumpkins.
There are two different river biomes.
dec: 7 hex: 7 bin: 111
dec: 11 hex: B bin: 1011
Frozen Rivers replace regular rivers, and generate only within snowy tundra biomes. As the name implies, the top layer of water is entirely frozen, though below the ice is the usual sand, gravel, and clay, though seagrass does not generate on the riverbed. While sugar cane can generate alongside a frozen riverbank, it quickly uproots itself after generation due to the water being frozen. Along with salmon and drowned, strays, rabbits, and polar bears can spawn in frozen rivers. No other hostile mobs can spawn, even underground.
Frozen rivers can cut through snowy tundra only, not its variants; a river that separates the snowy tundra from any other biome is only partially frozen.
|Java Edition Beta|
|August 18, 2011||Notch tweeted a screenshot of a revamped river biome.|
|1.8||Pre-release||Added rivers. Previously, were generated as part of the terrain generation algorithm.|
|1.13||18w16a||Renamed FrozenRiver to Frozen River.|
|Pocket Edition Alpha|
|0.1.0||Added biomes, including rivers.|
|0.13.0||build 1||Added rabbits, which can spawn in frozen rivers.|
|0.15.0||build 1||Added strays, which spawn in frozen river biomes.|
|1.0.0||alpha 0.17.0.1||Added polar bears, which can spawn in frozen rivers.|
|1.4.0||beta 184.108.40.206||Added drowned, which spawn in river biomes.|
|beta 220.127.116.11||Added salmon, which spawn in rivers.|
|Rivers now generate with seagrass.|
|1.13.0||beta 18.104.22.168||Squid can now spawn in rivers.|
- Lakes can technically still generate in the waters of rivers and frozen rivers, when either are used as buffet worlds. This can be more clearly seen in frozen river worlds, as holes in the ice.
- Regular rivers can still generate cutting through frozen rivers.
- Both types of rivers override ravines at or close to the surface level, causing the ravine to be abruptly cut off by a wall of stone. However, if the ravine is long enough, it may continue on the other side of the river.
- Oddly, ravines can generate underground in river biomes without being cut off.