Nhi Thanh Cave

Nhi Thanh Cave is a natural limestone cave in Tam Thanh Ward, Lang Son City, Lang Son Province, northern Vietnam. Discovered and developed in the late 18th century by official Ngo Thi Si, the cave extends about 500 meters through limestone karst. It is notable for its stalactites, underground stream, historic stone inscriptions and poems, and a small Buddhist shrine inside. Designated a national historic and scenic relic, it is a key cultural attraction in Lang Son.

Visitors enter through a large arched entrance in the limestone hillside in central Lang Son City and follow a paved, lit pathway through a series of chambers. Inside are stalactites and stalagmites, an underground stream, natural rock formations, and walls carved with poems and inscriptions from the 18th century. A small shrine area is located within the cave. The cave is relatively compact and explored on foot with steps and uneven surfaces.

Discovered and embellished in 1777-1780 by Ngo Thi Si, Governor of Lang Son under the Le Dynasty, who had the cave cleared, paths built, and poems and inscriptions carved on the walls. The cave later served as a scenic retreat and literary site, with additional inscriptions added by subsequent officials and scholars. Recognized as a National Historic and Scenic Relic.

The cave combines natural karst landscape with Vietnamese literary heritage through its preserved poems and calligraphy. It houses a Buddhist shrine and reflects traditional reverence for natural caves as spiritual and cultural spaces in northern Vietnam.