Laojun Mountain Nitrate Cave Ruins

Laojun Mountain Nitrate Cave Ruins

The Laojun Mountain Nitrate Cave Ruins are a National Key Cultural Relics Protection Unit.

The Laojun Mountain Nitrate Cave Ruins are a mining and refining site for nitrate production during the Ming and Qing dynasties in Sichuan. Located in Jiangyou City, Sichuan Province, they lie in the middle section of the Longmen Mountain Range in the northwest of the Sichuan Basin. The remains are primarily distributed across karst caves on peaks such as Yanjiayan, Daping Mountain, Konjac Mountain, Zangwangzhai Mountain, Zhazhai Mountain, Hejia Mountain, and Lishuping Peak. The distribution spans 21 kilometers from north to south, 14 kilometers east to west, covers a mountainous area of over 300 square kilometers, has a main peak elevation of 2,345.7 meters, a relative height difference of 1,676 meters, and lies within geographic coordinates of 104°54′11″–104°57′47″ E and 32°00′52″–32°03′41″ N.

In 2004, cultural heritage authorities discovered and investigated this group of nitrate cave sites. Based on analysis of stratigraphic superposition, nitrate mining underwent two large-scale operations prior to the 20th year of the Qianlong reign in the Qing Dynasty: the first likely occurred in the early Ming Dynasty, while the second large-scale operation took place during the Qianlong period, associated with the Dajin (Da and Xiao Jinshan) Campaigns. The *Zitong County Annals* by Zhu Lian of the Qing Dynasty recorded: “Laojun Mountain’s Chaoyang Cave is over 240 li to the west of the county. The mountain is steep and precipitous, and the cave lies amid the hanging cliffs of the central peak. A sky ladder was erected from the dry furnace flatland of Jiangyi, enabling descent via ladder to reach the cave, which is eight zhang high, six zhang wide and fifteen li deep, producing nitrates. Mining began in the 20th year of Qianlong, and extraction was managed nearby by Jiangyi. The Ziyi County stationed troops at the Chonghua Market pass to conduct patrols.” The *Long'an Prefecture Annals* (Daoguang Edition) also noted: “Nitrates are produced at Chaoyang Cave and Daxing Cave in Jiangyou, as well as in Pingwu, with annual production supplied to Xiaohé Camp.” Besides Chaoyang Cave and Daxing Cave (also known as Yanzidong), natural caves including Tianyudong, Gaoguandong, Xiniudong, Yaojingdong, Ganrendong, Niujiaodong, Jiuxiandong, Mingyuedong, Laojundong, and Zhonggoudong also bear remnants of nitrate production facilities.

The entrance to Chaoyang Cave is situated on the sheer cliff of Guanfengliang on Laojun Mountain, inside a natural karst cave. Access to the cave requires descending a suspended rope ladder of over 60 meters from a suitable point on the mountain ridge down the cliff face. The interior of the cave is 60–100 meters wide, up to 50 meters high, and approximately 3,500 meters long, sloping downward at about 40–50 degrees, with some sections exceeding 70 degrees. Inside the cave, remnants such as nitrate pits, water pools, and stoves can still be seen. Not far inside the entrance, there is a mountain spring with a relatively strong flow. There are nine working areas within the cave, ranging from several hundred to several thousand square meters, strewn with large amounts of nitrate residue and broken ceramic shards. These are divided into nine zones. Zone I is 300 meters long and contains three sets of nitrate pits. Pit 1# is circular, with an inner diameter of 250 cm and a remaining height of 100 cm, connected to a residual nitrate pit. Nitrate residue piles around it reach up to 16 meters high. Pit 2# is also circular, with an inner diameter of 230 cm and a height of 140 cm, located about 100 meters from Pit 1#. Below it is a circular receiving pit with a diameter of 120 cm and a depth of 50 cm, with nitrate channeled through bamboo pipes. Pit 3# is circular, with an inner diameter of 240 cm and a height of 120 cm, roughly 100 meters from Pit 2#, and also connects to a receiving pit below, which is 240 cm in diameter and 90 cm deep, with bamboo piping for nitrate transfer. At the bottom of the cave lies a passage whose entrance is 150 cm high and 100 cm wide, positioned 330 cm beneath the working surface. Supported by wooden beams and constructed with stacked stones, the tunnel is 20 meters long, spiraling downward, and sealed at the bottom with stone blocks. Other caves, such as Yanzidong (anciently called Daxingdong), Yaojingdong, Ganrendong, Niujiaodong, Gaoguandong, Mingyuedong, Xiniudong, and Tianyudong, all adapted their facilities according to their own spatial and slope conditions, but fundamentally include combinations of stoves, nitrate pits, receiving pits, water pools, and water channels. Scattered among them are also a small number of daily items, tool fragments used by ancient workers, and large amounts of mining slag.

Judging from the preserved production facilities, the scale of nitrate production here was extremely large—it is a site rich in cultural relics—and it can be preliminarily considered the largest cave nitrate site discovered in ancient China, as well as one of the important ancient raw material production bases for [gunpowder]. This holds significant value for researching the production of [gunpowder] materials in northwest Sichuan and mining and metallurgical production during the Ming and Qing periods.

In 2006, the Laojun Mountain Nitrate Cave Ruins were announced by the State Council as part of the sixth batch of National Key Cultural Relics Protection Units. They are cataloged under number 6-0183-1-183.

To strengthen the protection and management of the Laojun Mountain Nitrate Cave Ruins, in 2009, the Jiangyou City Establishment Committee approved the addition of the “Jiangyou City Laojun Mountain Nitrate Cave Ruins Protection Management Office” signboard under the Jiangyou City Cultural Relics Protection Management Institute, tasked with protecting the Laojun Mountain Nitrate Cave Ruins.

Protected Area: East to the line connecting Laojun Temple — Lingguan Tower — Wayaoping; South to the line connecting Mingyuedong — Gaoguandong — Xiniudong — Xiniugeng; West to the line connecting Hanluping — Zangwangzhai; North to the area south of Lishuping.

Further Reading:

· Sixth Batch of National Key Cultural Relics Protection Units