The Humongus Fungus
This single fungus is considered not only the largest fungus, but the largest organism in the world. 2.4 miles across, 3.7 square miles in area, and up to 8,650 years old, this species is found distributed throughout the northern hemisphere, but the specific biggest organism of the Honey Fungus is found in the Blue Mountains in Eastern Oregon and can only really be seen in entirety from thousands of feet in the air (picture 2).
Unfortunately, the grandeur of this fungus comes at a huge expense. It is severely parasitic and is a huge problem causing huge tree and plant die-offs in the areas it inhabits. Keep In mind, a lot of the fungus organism is the mycelial & rhizomoprhic network (root-like structure) that resides underground (picture 3). The mushrooms are only a small percentage of the organism (like an apple is the fruit of the whole apple tree). But if you do happen across the fruiting body, they are absolutely edible & delicious :) .