A blue whale, fascinating 30 meters in length and weighing 180 tons, was considered the largest living organism in the world until 1998. In 1998, a honey fungus was discovered on the slopes of the Blue Mountains in the US state of Oregon. Honey fungus is considered the largest organism in the world if we define an organism as a group of genetically identical cells that interact and have a common purpose. Home to this enormous being the “honey mushrooms” are the slopes of the Blue Mountains of Oregon. This giant occupies a territory of 965 acres. Honey fungus is a common name for several types of mushrooms from the Armillaria group. When a number of trees in the forest began to die off, scientists launched an investigation. They found that the roots of each tree examined were infected with this fungus. The distance between the farthest infected trees (victims of a genetically identical pathogen) was greater than 4 kilometers. The age of this fungal colony is estimated at 8000 years.