Longqing Gorge

Longqing Gorge, a core area of the Yanqing UNESCO Global Geopark, exemplifies North-China-type karst developed in 1.4-billion-year-old Precambrian dolostone of the Wumishan Formation. Dense structural joints and faults from the Mesozoic Yanshanian movement were later sculpted by Cenozoic karstification. The gorge walls preserve remarkable marine sedimentary structures—horizontal bedding, stromatolites, and tempestites—serving as an archive of ancient shallow-sea environments. A 72-meter-high double-curvature arch dam, completed in 1973, impounds a reservoir creating a 7-kilometer navigable waterway through steep cliffs and narrow gorges. Boat tours reveal classic karst scenery often compared to Guilin's Lijiang River, earning the nickname "Little Lijiang of Beijing." Notable features like the "Thread of Sky" (Yixiantian) fissure demonstrate active dissolution along vertical joint planes. This combination of well-preserved geological structures, active karst processes, and engineered water management makes Longqing Gorge an exceptional field site for understanding northern China's karst hydrogeology.

Great Wall

The Great Wall of China stands as the world’s largest man-made defensive structure. Far more than a single wall, it is an integrated system comprising walls, signal towers, barracks, and fortresses, built to protect ancient Chinese states against nomadic tribes from the northern steppe. Stretching approximately 21,196 kilometers across deserts, grasslands, and mountains like a gigantic dragon, the well-preserved sections we see today were mainly constructed during the Ming Dynasty (1368–1644).

Among the best-preserved Ming sections, Badaling in Beijing’s Yanqing District is the most representative (Figure 8). Serving as a vital military stronghold guarding the capital, it features 21 watchtowers along a 3,741-meter stretch of massive stone walls winding along rugged ridges. First opened to tourists in 1958, Badaling offers visitors an unparalleled opportunity to walk in the footsteps of history and experience the enduring grandeur of ancient China.