1) The assassination of Archduke Franz Ferdinand of Austria in 1914 triggered the start of World War I.

2) The Dead Sea, located between Jordan and Israel, is the lowest point on Earth's surface. Its saltwater is so dense that people can easily float on its surface.

3) The Super Bowl is the championship game of the National Football League (NFL) in the United States and is one of the most-watched television events each year.

4) Celtic mythology encompasses the folklore and legends of the Celtic peoples across Europe, particularly in regions like Ireland, Scotland, and Wales. It features deities like Morrigan, Cernunnos, and Brigid, and delves into themes of nature, magic, and the heroic exploits of legendary figures like Cu Chulainn.