In Thai, the language spoken by most people living around the park, Pù Mát means "high slope" — a plain description that undersells the ground it names. The park was created by prime ministerial Decision 174/2001/QĐ-TTg on 8 November 2001, upgrading an earlier preservation zone, and it covers 94,804 hectares spread across what were the districts of Tương Dương, Con Cuông and Anh Sơn. Nearly all of it, 89,517 hectares, is strictly protected; another 1,596 hectares are set aside for ecological recovery, and a buffer zone of 86,000 hectares wraps the whole. The park runs from 18°46′ to 19°12′ north and 104°24′ to 104°56′ east, along the Annamite spine that forms the frontier with Laos, and rises to 1,841 metres at Pu Mat itself. Botanists have confirmed 2,461 plant species inside its boundaries, some of them still awaiting formal description. The dominant vegetation is lowland evergreen forest: wet, dense, and slow to walk through.

Pù Mát is one of the most important places in Vietnam for mammals, and the reason is a list of names that most people have never heard. Surveys by the Social Forestry and Nature Conservation project in Nghệ An confirmed five mammals endemic to Indochina living here: the northern white-cheeked gibbon, the red-shanked douc, the saola, the Truong Son muntjac and the Annamite striped rabbit. The same work confirmed the continued presence of the Assam macaque, the Ussuri dhole, the Indochinese tiger and the Indian elephant. The saola carries this landscape in its scientific name — Pseudoryx nghetinhensis, for the provinces of Nghệ An and Hà Tĩnh — and in February 2004 the park hosted the conservation workshop convened to work out where the animal had gone and whether anything could still be done. Twenty years of searching later, nobody has answered the question.

Pù Mát is the core of something much larger. The Western Nghệ An Biosphere Reserve was designated in 2007 and recognised by UNESCO in 2011: roughly 1.3 million hectares across nine mountainous districts, sharing 440.8 kilometres of border with Laos, and the largest biosphere reserve in Southeast Asia. Pù Mát anchors it, with the Pù Huống and Pù Hoạt nature reserves alongside. Within that area, surveys count 130 mammal species, 295 birds, 84 fish, 54 amphibians and reptiles, and 39 kinds of bat. It is not empty country. Thai communities make up close to 69 percent of the population, alongside Khơ Mú, Kinh, Tày and H'Mông households and the small O Đu community, one of Vietnam's least numerous recognised groups. These are among the poorest districts in the province, which is the harder half of the conservation problem: the forest's protection and its neighbours' livelihoods are the same question asked twice.

What threatens the saola is not, in the main, the loss of forest. It is wire. Snares set across the hills for deer, pigs and civets catch whatever walks into them, and an animal with a population estimated at 50 to 300 individuals as of 2015 cannot absorb that. No trained scientist has ever observed a saola in the wild. The most recent confirmed record anywhere is a camera-trap photograph taken in central Vietnam in 2013, and there is genuine concern the species is already gone. A genomic study published in 2025 found that saola split long ago into two populations, the northern one centred on Pù Mát, Vũ Quang and Nakai-Nam Theun across the border in Laos — which is to say that if the animal survives at all, these ridges are among the few places it could be. The gibbons still sing here at dawn. That is the encouraging part, and it is worth holding onto, because the rest of the roll call has gone quiet.