Beijing has a total of 14 districts and two counties. In 2010, Xuanwu District was merged into Xicheng, and Chongwen District was merged into Dongcheng.
The two central districts are located within or just beyond Second Ring Road and make-up the old walled city of yesteryear. Along with Chaoyang District (a massively-sized district larger than the four central districts combined), this is where most visitors will find an overwhelming majority of the sights and lodging, dining and entertainment options. The districts are:

Xicheng District (西城区; Xīchéngqū)
It covers the northwestern part of the central city area to just beyond Second Ring Road in the west and up to Third Ring Road to the north.Beihai Park, Houhai,Beijing Zoo, and the National Concert Hall are located in this district.
Dongcheng District (东城区; Dōngchéngqū)
It covers the northeastern part of the central city area approximately up to Third Ring Road to the north and Second Ring Road to the east. The Forbidden City, Tiananmen Square and Beijing Central Station are located in this district.
Haidian District (海淀区; Hǎidiànqū)
It covers the northwest of the main urban area. About half of Haidian district is made up of theZhongguancunhigh technology industry and business cluster and Beijing's major concentration of universities.The Summer Palaceis located here.
Chaoyang District (朝阳区; Cháoyángqū)
covering a large area just east (and stretching both north and south) of the central city area stretching from ring two until beyond ring five to the east. Including CBD, the embassy area,Sanlitun, National Stadium (and other Olympic venues), Workers Stadium,Chaoyang Parkand Ritan Park
Other than Chaoyang and the southeast corner of Haidian, the following districts are not as popular for visitors.
Shijingshan District (石景山区; Shíjǐngshānqū)
It covers the area just west of the central city area. The Western Hills is located here.
Fengtai District (丰台区; Fēngtáiqū)
It covers the area south end west of Beijing. Beijing West Railway Station is located here.