1) The Mongol Empire, under the leadership of Genghis Khan, became the largest contiguous empire in history, spanning from Asia to Europe.

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 world's first stock exchange was established in Amsterdam in 1602.

4) A group of flamingos is called a "flamboyance."