北京什么样？北京应该什么样？怎么才能让归来的故人看出自己是回到了北京？要想说清这些问题，首先要知道老北京城的原貌。简单地说，老北京城是以皇宫为中心规划建设的。元大都的皇宫在城区的南部，商业区在北部，即所谓前朝后市。到明代北京便发展成了“宫城居中四面城，后 Beijing what? Beijing should be like? How can we make the return of the people see that they are back to Beijing? To clarify these issues, we must first know the original appearance of the old city of Beijing. In short, the old city of Beijing is the center of the planning and construction of the palace. Yuan most of the Royal Palace in the southern city, the commercial area in the north, the so-called antecedent. To the Ming Dynasty Beijing has developed into a "Miyagi center in the city, after