Though the heavily-fortified Hill 937, a ridge of the mountain Dong Ap Bia in central Vietnam near its western border with Laos, had little strategic value, US command ordered its capture by a frontal assault, only to abandon it soon thereafter.

Nevertheless, the Airborne troops took the hill through direct assault with heavy use of artillery and airstrikes, causing extensive casualties to the PAVN forces.

[6] Rising from the floor of the western A Sầu Valley, Ap Bia Mountain is a solitary massif, unconnected to the ridges of the surrounding Annamite Range.

The entire mountain is a rugged wilderness blanketed in double- and triple-canopy jungle, dense thickets of bamboo, and waist-high elephant grass.

The battle on Hamburger Hill occurred in May 1969, during Operation Apache Snow, the second part of a three-phased campaign intended to destroy PAVN Base Areas in the remote A Sầu Valley.

Lieutenant General Richard G. Stilwell, commander of XXIV Corps, amassed the equivalent of two divisions, and substantial artillery and air support, to once again launch a raid into the valley.

His plan called for the five battalions to "combat assault" into the valley by helicopter on 10 May 1969, and to search their assigned sectors for PAVN troops and supplies.

The overall plan of attack called for the Marines and the 3/5th Cavalry to reconnaissance in force toward the Laotian border, while the ARVN units cut the highway through the base of the valley.

The US and the ARVN units participating in Apache Snow knew, based on existing intelligence information and previous experience in the A Sầu, that the operation was likely to encounter serious resistance from the PAVN.

Aerial surveillance was difficult, and US battalion commanders had to generate their own tactical intelligence by combat patrols, capturing equipment, installations, documents, and occasionally prisoners of war to provide the raw data from which to draw their assessment of the PAVN order of battle and dispositions.

Its units experienced only light contact on the first day, but documents captured by 3/187th indicated that the PAVN 29th Regiment, nicknamed the "Pride of Ho Chi Minh" and a veteran of the 1968 Battle of Hue, was somewhere in the valley.

Past experience in many of the larger encounters with PAVN indicated they would resist violently for a short time and then withdraw before the Americans brought overwhelming firepower to bear against them.

Honeycutt anticipated his battalion had sufficient capability to carry out a reconnaissance on Hill 937 without further reinforcement, although he did request that the brigade reserve, his own Company B, be released to his control.

Rather than retreat, the PAVN in the valley determined to stand and to fight in a series of well-prepared concentric bunker positions on Hill 937.

Having made no significant contacts in its area of operations, at midday on 13 May, the 3rd Brigade commander, Conmy, decided it would move to cut off PAVN reinforcement from Laos and to assist Honeycutt by attacking Hill 937 from the south.

Steep gradients and dense vegetation provided few natural landing zones (LZs) in the vicinity of the mountain and made helicopter redeployments impractical.

PAVN soldiers, able to maneuver freely around the LZs, shot down or damaged numerous helicopters with small arms fire, Rocket-propelled grenades, and crew-served weapons.

Napalm, recoilless rifle fire, and dogged squad and platoon-level actions eventually accounted for the reduction of most fortifications, though at a pace and price thoroughly unanticipated by American forces.

From a light observation helicopter, the battalion commander attempted to coordinate the movements of the other companies into a final assault, but an exceptionally intense thunderstorm reduced visibility to zero and ended the fighting.

Because of the heavy casualties already sustained by his units and under pressure from the unwanted attention of the press, Zais seriously considered discontinuing the attack but decided otherwise.

Author Andrew Wiest wrote in 2007, particularly based on the statements by Abrams in "The Abrams Tapes," says its role in the final assault was as follows: The unit was positioned on a stretch of the PAVN defense line that was lightly defended, and sent a scout party to test the forward enemy lines earlier than the proposed assault time; this party was quickly able to discern the minimal enemy strength.

[9] As it had no real military significance aside from the presence of the PAVN on it, Major General John M. Wright who replaced MG Zais as commander of the 101st Airborne in May abandoned the hill on 5 June as the operations in the valley were concluded.

[11][12] The debate over Hamburger Hill reached the United States Congress, with particularly severe criticism of military leadership by Senators Edward Kennedy, George McGovern, and Stephen M. Young.