Rivers are water body structures that generate in Swamplands and Sludge Plains biomes. They are long, twisting rivers of water only around five to six blocks wide. The land on the sides of the rivers are level with the water, allowing an easy way to get out. In Swamplands biomes, these rivers are dark bluish-green and often accompanied by Swamp Reeds generating in and around the water, as well as occasional patches of Algae Blocks. In Sludge Plains biomes, the rivers are brown and may contain plenty of Middle Gem Ores.