Call it Chu Pong or Chu Prong; both names attach to the same tangle of high, broken country in what is now Chư Prông District of Gia Lai province. The massif sits north of the Gia Lai river and south of the Ia Krel, and it is best understood not as a mountain in the postcard sense but as complex topography — a region rather than an object, with no single crest that would tell you when you had arrived. The Central Highlands plateaus around it run generally between 500 and 600 meters. Off its northeastern flank runs the Ia Drang, a river that rises in the hills south of Pleiku, bends southwest through the district, crosses into Cambodia's Ratanakiri province and eventually feeds the Srepok and then the Mekong. Water leaves this mountain heading away from Vietnam. So, for a decade, did soldiers.

There were few reliable roads into the area, which is precisely what recommended it. The People's Army of Vietnam and allied guerrilla forces built base areas in and behind the massif, and they were supplied in part through Cambodia — by ships unloading at Sihanoukville and trucks running inland along what came to be called the Sihanouk Trail, a system that moved some 29,000 tons of military cargo between late 1966 and 1969 under the cover of Cambodian neutrality. American ground forces were not permitted to follow across that border. A unit could fight all day on the eastern slopes and watch its opponent withdraw west into territory it was forbidden to enter, there to rest, absorb replacements and come back. The mountain's military worth had almost nothing to do with its height. It came from a line drawn by French administrators decades earlier that the war was not officially allowed to cross.

Look for LZ X-Ray or LZ Albany on any map and you will not find them. They were clearings — the kind that open at random in this forest — chosen for the single reason that a helicopter could get into them, and christened on the spot from the NATO phonetic alphabet. X-Ray lay at the eastern base of the massif, bordered on the west by a dry creek bed, with the Ia Drang about two kilometers to the northwest. It was roughly the size of a misshapen football field, some hundred meters across, and only eight Hueys fit into it at once. Albany was another clearing about two and a half kilometers northeast. In November 1965 those two patches of grass became the site of the first major battle between American and North Vietnamese regular units, and the names outlived the fighting by decades. The grass closed over both of them within a few seasons.

Unable to occupy the massif, American forces tried to remove it — or at least the forest that made it useful. In 1966, Operation Hot Tip attempted to burn the mountain down. Napalm and the desiccant Agent Blue came first in mid-February; in mid-March, eleven more napalm strikes and M-35 incendiary bomblets were delivered from B-52s. Much of the vegetation died. The fire never became self-sustaining, which was the point of the exercise, and the operation is remembered as a failure of its own theory. Agent Blue was an arsenic compound, cacodylic acid in water, sprayed across Vietnam and Laos to the tune of roughly four million gallons between 1962 and 1971 and used chiefly to kill rice. That detail matters here, because rice on these slopes was grown by the Jarai — the largest of the Central Highlands peoples known collectively as Degar, matrilineal, speaking an Austronesian language kin to Cham and to the languages of Indonesia and the Philippines. They did not evacuate when the aircraft came. There was nowhere in particular to go.

Chư Prông District covers about 1,694 square kilometers and held 143,463 people at the end of 2024, nearly double its 2003 population of 76,255. The red basalt soil that once anchored the forest turned out to be extraordinary farmland — the Central Highlands hold around 60 percent of Vietnam's basalt reserves and roughly 80 percent of its coffee acreage — and coffee and rubber now run in ordered rows across ground that was mapped in 1965 only by what could be flown over it. Much of that growth came with Kinh settlement from the lowlands, which over four decades made the region's indigenous peoples a minority in their own highlands. The massif is still there, still crossing into Cambodia, still without a summit worth naming. It is simply a large green mountain again, and the most interesting thing about it is how briefly, and how violently, it was something else.