The largest rainforest in the world is the Amazon Rainforest. Spanning across several countries in South America, including Brazil, Peru, Colombia, and Venezuela, it covers more than 5.5 million square kilometers (2.1 million square miles). The Amazon is known for its unparalleled biodiversity, hosting millions of species of plants, animals, and insects, many of which are not found anywhere else. It plays a crucial role in regulating the Earth's climate by absorbing carbon dioxide and producing oxygen. The rainforest also has significant cultural importance for Indigenous peoples who have lived there for centuries.