Phase 2 of the battle to destroy Hill C1 begins.

The second offensive against this stronghold was the longest, most arduous, and fiercest. On April 11, 1954, the second phase of the battle to destroy Hill C1 began. Company 811 (Battalion 888, Regiment 176, Division 316) was assigned the task of defending and fighting on this stronghold; Regiment 98, which fought in the first phase (from March 30 to April 10), was ordered to withdraw to the rear.

In the second offensive, our troops successfully employed the "sneak attack" tactic, digging trenches and secretly approaching deep into the enemy's stronghold, giving the French the impression that our soldiers had "emerged from underground" right in the middle of the enemy's fort. (In the photo: The battle of concealment taking place on Hill C. Photo: VNA archives)

The balance of power between us and the enemy on Hill C1.

Hill C1 was part of the system of defensive high points on the eastern hills of the French Dien Bien Phu fortified complex; it served as a screen protecting the central area of ​​Muong Thanh, and was garrisoned by Company 3 of Battalion 1, 13th Foreign Legion Half-Brigade (13DBLE).

The stronghold was built on Hill 493, a relatively solid structure with a dense and complex system of fences and obstacles, with the eastern side reaching up to 100 meters thick; a multi-layered system of bunkers and trenches forming a circular defensive position. The command bunker was located in the Flagpole bunker, the highest point of the stronghold. Furthermore, because this was the enemy's main defensive direction, any combat would receive significant firepower and manpower support from nearby strongholds and the central command of the fortified complex.

The battle to destroy Hill C1, commanded by Regiment Commander Vu Lang (E98, 316th Division), lasted 32 days and was divided into two phases: Phase 1, from March 30 to April 10, 1954, was undertaken by Regiment 98; Phase 2, from April 11 to April 30, 1954, was undertaken by Company 811 (Battalion 888, Regiment 176, 316th Division).

Under attack, the enemy in positions on Hill C scattered in disarray, while our assault troops in the trenches used their rifles to snipe at the enemy. Photo: VNA archives.

Comparing the balance of power between us and the enemy on Hill C1, the enemy had a significant advantage over us:

Regarding forces: The enemy had two well-trained companies recently reinforced from Hanoi , so they were very energetic; in addition, they received strong support from two paratrooper battalions on the adjacent C2 Hill and Mam Xoi Hill. Meanwhile: We only had one company (C811), and the health of our soldiers had deteriorated due to continuous fighting at Dien Bien Phu since the end of October 1953.

Regarding the battlefield: The enemy occupied 2/3 of the hill to the south, a larger area and a higher elevation; our position was only 1/3 of the hill to the north and narrower than the enemy's.

Regarding weaponry: The enemy was far superior to us. They possessed flamethrowers, a formidable weapon used for the first time in Vietnam and only in the Battle of Dien Bien Phu. The enemy also had artillery support from Hong Cum, four-barreled heavy machine guns on the adjacent C2 hill, and at the Muong Thanh bridgehead, only a few hundred meters from our position. Furthermore, enemy aircraft regularly dropped bombs, including napalm bombs, on the positions of Company 811.

Company 811 was ordered to take up defensive positions on Hill C1, while Regiment 98 withdrew to the rear.

Even if the presence of our troops on Hill C1 was unacceptable to the enemy, we still needed to maintain this high ground as a springboard for the final offensive. On April 11, 1954, only sporadic fighting took place. Both the enemy and our troops had to concentrate all their efforts on consolidating their footholds on the hill; bombs and bullets had destroyed all combat fortifications and hiding places. The enemy had to bring in the third company of the 2nd Foreign Legion Paratrooper Battalion, which had just arrived in Muong Thanh, to replace the forces that had fought all night and were now completely exhausted.

At dawn on April 11, 1954, both sides were quiet. The enemy was preparing to attack, while we were at a disadvantage, resolutely preparing for a counter-offensive to retake the position. In a bunker on the right slope of Hill C1, Battalion Commander Hoang Vuong was discussing with his officers the decision to retake the Flagpole.

The encroaching trenches brought further calamities to the French army. The barbed wire fences and minefields of the stronghold now became obstacles protecting our troops. Photo: VNA archives.

According to the campaign command's plan, the 98th Regiment was ordered to withdraw to the rear to consolidate and prepare for the upcoming general offensive. On the afternoon of April 11, 1954, while coordinating with the 304th Division in the battle at Hong Cum, the 888th Battalion (316th Division) was ordered to march to reinforce the 98th Regiment. Due to operational requirements, Regiment Commander Vu Lang decided to deploy only Company 811 of the 888th Battalion to defend and fight on Hill C1. Company 811 defended Hill C1 for twenty consecutive days, until the stronghold was completely destroyed at the end of April.

On the afternoon of April 11, 1954, Company 811 constructed trenches, gun emplacements, and sleeping bunkers, then used barbed wire and enemy mines to mark the boundary between our forces and the enemy.

The battle of April 10th and 11th, 1954, was Bigeard's final major counterattack on the eastern hills. The enemy was forced to alternately deploy companies to defend the inner hills. Both sides understood each other well and agreed to temporarily maintain the status quo. Occasionally, there were grenade exchanges, bursts of machine gun fire, flamethrowers, and lightning-fast raids.

For 20 days and nights, from April 11th to 30th, 1954, both sides at the C1 stronghold launched numerous attacks, fighting for every inch of land, every gun emplacement, every section of trench, but neither side could gain the upper hand.

[Source: VNA; Book: General Vo Nguyen Giap: Complete Collection of Memoirs, People's Army Publishing House, Hanoi, 2010, p. 1043; Dien Bien Phu Victory - Chronicle Volume 2, People's Army Publishing House, Hanoi 2024, pp. 146, 147]

Source: https://kinhtedothi.vn/ngay-11-4-1954-bat-dau-dot-2-tran-danh-tieu-diet-doi-c1.html