Yggdrasil is a colossal ash tree in Norse mythology that connects the nine worlds, serving as a central axis of the universe. It is often depicted as a symbol of life, death, and rebirth, with its roots and branches extending into various realms, including Asgard, the home of the gods, and Niflheim, the realm of the dead. The tree is not only a physical structure but also a representation of the interconnectedness of all beings. Creatures like the Norse dragon Nidhogg gnaw at its roots, while the wise Norns weave the fates of gods and men beneath its branches, emphasizing the importance of Yggdrasil in the cosmic order.