1) The national animal of Australia is the kangaroo.

2) The highest-grossing concert tour of all time is U2's "360° Tour," which earned over $735 million in ticket sales.

3) The Appalachian Mountains, running along the eastern coast of the United States, are one of the oldest mountain ranges in the world.

4) Aztec mythology, originating from ancient Mesoamerica, includes deities like Quetzalcoatl, Huitzilopochtli, and Tlaloc. It explores concepts of creation, sacrifice, and the cyclical nature of time, with intricate cosmology and rituals forming a significant part of Aztec religious beliefs and practices.