1. The world's first underground railway system was in London on 1863. As for the earth, the age of the universe is about/kloc-0.5 billion years, and the age of the earth is 4.6 billion years.

According to current scientific speculation, living things appeared 3.3 billion years ago. As for humans, it should be Australopithecus at the earliest, with a history of about 4 to 3 million years.

3. The earliest characters in the world (cuneiform characters) appeared about 5000 ~ 6000 years ago; The earliest writing in China is Oracle Bone Inscriptions in Shang Dynasty, which is 3000 years ago.