说到旅游,一直以来,北方人都喜欢去南方,因为那边四季如春,鲜花常开,绿草茵茵,更有自古至今繁华不败城市和文化,岂不知,早在1300多年前,北方有一个的海东盛国,疆域辽阔,人口达10万,是中世纪亚洲仅次于长安的的第二大都市。她就是渤海国,都城上京龙泉府,20位皇帝,共计建国229 Speaking of tourism, the northerners always like to go to the south, because there are four seasons such as spring, flowers often open, green grass Yan, more ancient and bustling from the ancient city and culture, do you not know, as early as 1300 years ago, There is a sea east of the Grand State, a vast territory, population of 100,000, is the second largest city in Asia after Middle Ages in Asia. She is the Bohai Sea, the capital of Beijing Longquan House, 20 emperors, a total of founding of 229