11 of the most famous riddles in history

Even 4,000 years ago, people tested one another’s critical thinking skills with riddles and logic puzzles. This ancient civilisation, located in what is today the country of Iraq, left us with one of the earliest known examples of a written riddle. (Ancient Sumer is also the civilisation with the oldest surviving writing system that we know of!) Here is the riddle: “There is a house. One enters it blind and comes out seeing. What is it?”