Built during the late Song Dynasty and the early Yuan Dynasty，the Old Town of Lijiang has no city walls. It rests on Lion Mountain in the west and borders on Elephant Mountain in the north. Surrounded by green hills，it looks like a jade ink slab，thus the name Dayan Town ("yan" homophonously for ink slab).The center of the town is the town is the Sifang Street surrounded by five main streets (Xinhua，Wuyi，Qiyi， Xinyi，and Guangyi) leading in all directions. Among these main streets is a web of alleys and paths which run through the whole town.
The old town has made good use of water from the Black Dragon Poo1.Indeed，the crystal clear water from the pool flows through the houses of the town in three major separate rivers (East，Middle and West Rivers) and many minor rivers. Thus，the town is uniquely characterized as "rivers winding through every house and willows weeping before every family" ，a well-known scene of South China. Rivers and bridges can be seen everywhere in the town；so，the number of bridges within such a small area may rank first in China. Because of this，the town is called "Gaoyuan Gusu" (Plateau Suzhou) .The roads in the town are paved with mottled slabs，easy for walking and cleaning. The common dwellings are mostly two-storied wooden buildings designed as three houses and one screen wall，or as four houses and five courtyards，a combination of the excellent architectural styles of such nationalities as the Han，Bai，and Tibetan. The wooden framework joined with tenons and mortises as found in Naxi buildings is so special that a house does not fall even when its walls have collapsed. As a result，the old town has withstood earthquakes. Mu's Mansion (the mansion of the magistrate Mu) in the town was rebuilt after the earthquake of 1996.The original mansion was praised by Xu Xiake："the magnificence of the mansion can be compared to that of a prince's residence. " Its majesty，grandness and spectacularity remind people of the cultural prosperity and the special power of chieftain Mu among other chieftains in Southwest China for the 470 years and 22 generations during the Ming and Qing dynasties. Now，the Old Town of Lijiang has become a famous national historical and cultural city for its long history，rich cultural relics and historic sites，and brilliant ethnic cultures. In 1997，it was declared by the UNESCO as a cultural world heritage.
In Yuquan (Jade Spring) Park at the edge of the town are such Ming and Qing architectural complexes as Wufeng Pavilion (Five Phoenix Pavilion)，Guangbi Pavilion，Jietuoling Gate Tower，and Deyue Pavilion. Beside the park are institutions like Lijiang Museum of Dongba Culture and Institute of Dongba Culture where the artistic charm of the Dongba hieroglyphics，the only living hieroglyphics in the world，appeal to visitors. In August 2003，Dongba classics and literature were listed among the Written World Heritages. Roaming in the town，one catches sight of couplets written in Dongba hieroglyphics from time to time and enjoys the plain and elegant ancient Naxi music.
In the township of Baisha，eight km north of Dayan，and the township of Shuhe，four km northwest of the old town，is another part of the old town：two ancient residential complexes-Dabaoji Palace and Liuli Palace where Baisha frescoes are still found and are both national cultlural and historical relics.