Lao Cai was the capital of Yellow Lotus Mountain Province, located at the confluence of the Red River and Nanxi River. With a railway to Hanoi, highways, and access to Red River water transport, it was a vital gateway to northwestern Vietnam—and naturally, a place that had to be taken.
Previously, China's military movements had shifted from covert to overt, no longer concealed in any way. Vietnam had naturally noticed and made its own preparations.
The Vietnamese forces organized defenses across Lao Cai, Xiaocao, and 475 Highland, intending to use the Red River as a barrier and rely on the high ground to hold their positions and halt the advance of Chinese troops. They had built large numbers of trenches, permanent shelters, and earthen-and-wood firing positions around Lao Cai, and had prepared firing plans for the main targets and routes of advance.
The Vietnamese 345th Division defended Lao Cai and its surrounding areas. It could not be called an ace army unit, but it was still considered elite.
The overall battle plan was for the 13th Army to attack Basha and Bao Thang while coordinating with the 14th Army in the assault on Lao Cai. The 14th Army's deployment had the 40th Division attacking Lao Cai, the 42nd Division attacking the area from Lamin to Ban Lao to sever the connection between Lao Cai and Mengkang, and the 41st Division attacking Mengkang and Falong.
In short, the plan was to attack the major towns along the border. The same was true across the entire front, including the other armies on the eastern front attacking places such as Lang Son and Cao Bang. That was the grand strategy; the specific battle plans also had to fully account for enemy reinforcements and coordinated operations...
The 40th Division's mission was to attack Lao