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.
Nanjian Yi Autonomous County (Nanjian County for short) is located in the west of Yunnan Province and the southern end of Dali Bai Autonomous Prefecture, which is located in the joint of Dali, Lincang and Pu'er counties. The original name "Pu Yu", when the Tang Dynasty Mengshe Zhao, because Nanjian is located in the south of the political district, Jiajian water, so the name Nanjian. Nanjian County is bounded by Midu County in the east, Jingdong County in the south, Fengqing County in the west, Lancang River in the southwest and Weishan County in the north. By 2013, Nanjian County has jurisdiction over 5 towns and 3 townships, covering an area of 1731.63 square kilometers, with a total population of 223100. The tourism resources of Nanjian County are mainly natural landscape and cultural landscape, including Wuliangshan National Nature Reserve, Lingbaoshan National Forest Park, Lushan Temple, Shidong Temple, Baiyun Temple, Li Literature site and so on. September 2, 2018