In the foggy early morning, Zhiyin Mountain is like a giant beast, looming in the thick fog. The peaks are not high, but the terrain is steep and the forests are lush, giving anyone who sets foot here a sense of oppression. In this seemingly calm mountain forest, there is a hidden tension in the border field. For decades, it has been a key point on the Sino-Vietnamese border and has been the focus of conflicts on several occasions.
In addition to the well-known old mountain, Zhiyin Mountain also bears an indelible historical imprint. Once upon a time, this mountainous region witnessed the tenacity and glory of the heroic army, and the military tactics and strategic layout were fully developed here. In 1984, a crucial battle was fought here, and our army decided to regain lost territory and re-establish the security of the border. At that time, the strategic choice was not only a battle for physical space, but also a contest of will and wisdom.
The geographical and climatic characteristics of Zheyin Mountain
Located in Malipo County, Yunnan Province, China, the main peak reaches an altitude of 1,250 meters, and is often referred to as the "1250 Highland" by local military personnel. The terrain of the region is known for its ruggedness and complexity, and its changeable weather presents additional challenges to the war. Due to its high altitude, the mountain is covered by dense fog all year round, especially in the wet season, when the thick fog arrives almost every morning as scheduled and lasts until the afternoon. This low-visibility weather condition greatly affected the line of sight and made it extremely difficult for the garrison to conduct daily patrols or make tactical deployments.
In March 1979, in accordance with previous international commitments, our troops were withdrawn from the Zheyin Mountain area. However, the Vietnamese army did not miss this opportunity and quickly crossed the border line and occupied this strategic location. This action by the Vietnamese army not only quickly changed the military balance in the border area, but also directly threatened the security of nearby Malipo County and its surrounding areas. After occupying the Yin Son, the Vietnamese army quickly began to build fortifications at the top of the hill and in key areas around it in order to consolidate its newly acquired positions.
During this period, the weather conditions on Zheyin Mountain are still changeable. Dense fog and occasional torrential rains make the mountainous terrain even more difficult to navigate. The Vietnamese army had to take these natural factors into account when building defenses, and they took advantage of the uncertainty of the weather and the complexity of the terrain to set up concealed sentinel posts and mine arrays. Under the cover of fog, these sentinels and minefields are often difficult to detect, creating an additional obstacle to any attempt at counter-offensive.
At the same time, our army had a clear understanding of the importance of Jiyin Mountain, so it conducted in-depth research and preparation on how to regain the lost territory. Under extremely difficult conditions, our engineers and scouts carefully reconnoitred the defensive layout of the Vietnamese army at Zheyin Mountain. Not only do they have to face the dual challenges of terrain and weather, but they also have to be constantly vigilant against Vietnamese patrols and mines planted in dense forests.
In the course of reconnaissance and surveillance day after day, our army gradually built a detailed map of the defense of the Vietnamese army on the Yin Mountain.
The strategic layout of the Vietnamese army and the response of our army
The Vietnamese army was elaborate and intricately deployed on the No. 10 high ground of the main peak of Zheyin Mountain, and dense anti-infantry minefields spread along the national border, forming an impenetrable defensive line. These minefields are made up of many types of mines, including anti-personnel and obstructive mines, which are strategically placed to create maximum damage and delay. In addition to mines, the Vietnamese army also erected barbed wire, deep trenches, and barriers made of logs and stones, which not only hindered the movement of mechanized equipment, but also greatly restricted the rapid movement of infantry.
Further, in and around the main peak, the Vietnamese army used local materials to build multiple reinforced concrete fortifications, which were carefully designed to blend in with their surroundings and be difficult to observe directly. Inside these fortifications were firing holes and viewing windows, which allowed the Vietnamese army to conduct an organized defense. In addition, these fortifications were connected by a series of trenches and communication trenches, forming a mutually supportive battle network.
In terms of firepower allocation, the Vietnamese army skillfully took advantage of the favorable conditions of the terrain and deployed a multi-level and multi-angle firepower coverage system. This system covers machine gun nests and mortar positions, which can carry out frontal and flank fire on the attacking side, forming a cross-fire network, effectively improving the overall combat effectiveness of the defensive line. This firepower layout exposes any enemy forces that try to approach the mountain to continuous fire.
Strategically, the establishment of this defense system enabled the Vietnamese army to effectively control the key access roads that stretched south from the Đễn Son to the Yang Van area. As a result, this area has become a strategic point for the Vietnamese army, and its firepower network covers an area more than 10 kilometers deep in the mainland. Due to the wide range of firepower of the Vietnamese army, the inhabitants of the area and our logistical supply lines are under constant threat, which poses a serious challenge to our tactical layout and regional security.
In order to effectively respond to this situation, our army had to reassess its tactical deployment and operational plans in the region. While trying to penetrate this complex defensive system, our forces began to rely more on indirect firepower and air support to weaken the Vietnamese defenses. In addition, special forces and engineering units have been mobilized to clear mines and other explosive obstacles to ensure the safe advance of troops in the main direction of attack.
The Battle of the Two Mountains unfolds
In the spring of 1984, tensions on the Sino-Vietnamese border intensified. In this year, the Chinese army underwent a large-scale strategic realignment to regain lost frontier positions. On April 28, the 40th Division of the 14th Army, after careful planning and preparation, successfully regained the strategically important Laoshan. This move is not only an important recovery of previously lost territory, but also a clear psychological and strategic blow to the enemy. Two days later, on April 30, also after careful preparation and strategic deployment, the 31st Division of the 11th Army successfully recaptured Zheyin Mountain, further strengthening China's defense capability in the border area.
The success of these two battles was not only a military victory, but also played a great role in enhancing the security and stability of the border areas. By regaining control of these two key heights, the Chinese army effectively weakened the Vietnamese army's frontline defenses, while also rebuilding the defense system along the border. The strategic location of Lao Son and Zheyin Mountain makes them powerful points for controlling the surrounding area, and their highland advantage can be used to monitor and defend against any potential Vietnamese attack.
Despite the victory in the Battle of Lao Son, the Chinese army faced occasional attacks and attacks by the Vietnamese army after the war. The Vietnamese army used guerrilla tactics, taking advantage of the complexity of the jungle and terrain to carry out a quick strike and then retreat. This tactic not only made it difficult for the Chinese army to pursue effectively, but also made the situation in the border area tense at all times. These small but frequent attacks by the Vietnamese army tried to drag down the Chinese army by draining the resources and morale of the Chinese army.
In response to this tactic of the Vietnamese army, the Chinese army has made strategic adjustments, strengthening the protection of important areas and patrolling the border line. Especially in the areas of Lao Son and Gi Yin Son, the army has not only strengthened its conventional defense deployments, but also set up multiple monitoring and response points to allow for a rapid response to any potential Vietnamese military activity. In addition, the Chinese army also took advantage of its terrain and geographic information to arrange a series of ambush circles and anti-guerrilla tactics in an attempt to weaken the Vietnamese army's guerrilla advantage.
The stability and influence of the latter Yin Mountain
After the end of the Battle of Zheyin Mountain, with the gradual consolidation of our army's control in the area, the border security has been significantly improved, and the security threat in the Yangwan area has been effectively alleviated. Through a series of well-planned and resolutely executed military operations, the situation in the region has changed from previous tension and instability to relative calm, laying the foundation for long-term security in the border area.
In this process, the reinforcement of our army's regional defense is not only reflected in the optimization of the tactical level, but also includes the continuous improvement and maintenance of defense facilities. After the battles of Zheyin Mountain and Laoshan Mountain, our army established a series of new monitoring systems and rapid response mechanisms in these key areas. This includes, but is not limited to, new watchtowers, reinforced bunkers, and efficient communications facilities, all of which greatly improve our military's perception and response to any potential threats.
In addition, our military has strengthened ties with local communities and improved the efficiency of intelligence gathering by establishing closer cooperative relationships. This not only helps the military to keep abreast of the dynamics of the border, but also strengthens the people's sense of trust in national security. Through militia training and equipment upgrades, border residents are also part of the defense system, and their participation adds an extra layer of security to the border.
"Drag down tactics" and "two-mountain round battle" strategies
In the face of the "drag down tactics" adopted by the Vietnamese army in Lao Son, the Chinese high-level leaders decided to implement a completely new strategic plan, that is, the "two-mountain round battle" strategy, after a comprehensive assessment of the military situation in the border area. This strategy involves the five military regions – Nanjing, Wuhan, Lanzhou, Beijing and Shenyang – who will take turns sending elite troops to the Yunnan border region to maintain a high level of combat readiness and effectively respond to the constant provocations of the Vietnamese army.
From the end of 1984 onwards, this strategic plan was rapidly implemented. First of all, the troops sent by the Nanjing Military Region reached the Yinshan and Laoshan areas, where they reinforced the existing fortifications and set up new observation posts and artillery positions at key points. Subsequently, the troops of the Wuhan Military Region took over from the Nanjing Military Region, bringing with them their rich experience in mountain warfare and jungle warfare, which brought new impetus to the effectiveness of the overall defense system.
The troops of the Lanzhou Military District, with their expertise in fighting at high altitudes, have strengthened the defense of the border line. They are particularly sensitive to the guerrilla tactics used by the Vietnamese army, and have deployed several rapid response teams that are ready to respond to possible surprise or infiltration operations by the Vietnamese army.
The Beijing and Shenyang Military Regions, on the other hand, have focused on improving their tactical coordination and logistical support capabilities to ensure that front-line troops can continue to receive the necessary supplies and ammunition. In addition, they introduced new communications equipment and reconnaissance technologies to improve the accuracy of battlefield surveillance and target acquisition.
Through this rotation mechanism, not only did the combat fatigue of the troops remain within a controllable range, but also effectively used the characteristics and advantages of various military regions to form a powerful response to the tactics of the Vietnamese army. The implementation of this strategy has enabled the Chinese side to exert continuous pressure in the border areas, effectively preventing further encroachment and harassment by the Vietnamese army.
During the implementation of this "two-mountain round battle" strategy, the combat capability of the Chinese troops in the Zheyin Mountain and Laoshan areas has been significantly improved. Due to the frequent turnover of troops, each group of recruits will receive detailed intelligence and tactical training for the current combat situation before entering the war zone, ensuring that they can quickly adapt to the battlefield environment and carry out their tasks.
In addition, in this way, experience and information between troops are quickly exchanged and updated, increasing the flexibility and adaptability of the entire front. In the course of rotation, each military region was able to learn new tactical knowledge from the experience of the previous batch of troops, and this continuous process of learning and applying it has greatly enhanced the overall combat efficiency. The "two-mountain round war" strategy, which lasted for nearly five years, finally ended in early 1989.
Li Shiyuan.Battlefield interview in Laoshan and Zheyinshan[J].China Reporter,1985(8):28-29