We often see the word "crossing" in science fiction films, which is one of the common themes of science fiction films, and the most impressive is the series of science fiction films such as "Star Trek" and "terminator" which are closely related to crossing.

Crossing is also one of the dreams of many people. With this black technology, people can not only cross back to become millionaires, but also easily change a person's future.

So, in the long history of mankind, has there ever been anything about crossing? Today, I'd like to introduce to you some famous cultural relics in history. Each of these relics looks like a crossing object, and there's no sense of disobeying it in modern times.