There is a great saying goes that " Roma is not built in one day! " Though this saying mainly tell us that we should be patient to do everything, the name Roma always gives me an imagination of a big city with numerous people in ancient time. Fortunately, we have a city as famous as Roma in the old time. Maybe you have gussesed what city I will introduce to you. It's Changan, but also is known as Xi'an. YOu can imagine that there were over 1 million people lived in Xi'an 1500 years ago, and the number today is around 12 million. The rich history left a lot of marvelous heritages for us. Every year, people around the wrold crowd to this international city. They bring their culture here and take Chinese culture back to their countries. Culture is the best bridge between peopel from different countries. This makes Xi'an to be a city features both modern and historical achievements.