A mesa is an isolated, flat-topped elevation, ridge or hill, which is bounded from all sides by steep escarpments and stands distinctly above a surrounding plain. Mesas characteristically consist of flat-lying soft sedimentary rocks capped by a more resistant layer or layers of harder rock, e.g. shales overlain by sandstones. The resistant layer acts as a caprock that forms the flat summit of a mesa. The caprock can consist of either sedimentary rocks such as sandstone and limestone; dissected lava flows; or a deeply eroded duricrust. Unlike plateau, whose usage does not imply horizontal layers of bedrock, e.g. Tibetan Plateau, the term mesa applies exclusively to the landforms built of flat-lying strata. Instead, flat-topped plateaus are specifically known as tablelands.
Bazhou is a county-level city hosted by Langfang City, and one of the first expanding counties and cities in Hebei Province, located in the east of Jizhong Plain in Hebei Province, located in the center of the triangle zone of Beijing, Tianjin and Bao, and belongs to the urban agglomeration around Beijing, Tianjin and Bohai Sea. It is 80 kilometers north of the capital Beijing, 70 kilometers east of the seaport city of Tianjin, and 65 kilometers west of the ancient city of Baoding. Has a long history, Qin belongs to Guangyang County, Han Zhuojun Yichang County, Zhou Xiande six years after the five dynasties (AD 959) built Bazhou. After Jin, Yuan, Ming and Qing dynasties, all of them were Zhili Guan. In 1913, the prefecture was changed into a county, which is a special zone of Jingzhao. In February 1990, the State Council approved the withdrawal of counties and the establishment of cities, which opened a new page in the history of Bazhou.