In the Canadian French spoken by the Métis, the pine is called cyprès,[6] although it is not a true cypress tree.

This makes the Cypress Hills the highest point between the Rockies and Labrador[8] They are the remnant of a more widespread plateau, most of which has been removed by erosion.

That formation was deposited by rivers that flowed from the mountains of southwestern Alberta and northwestern Montana during late Eocene to middle Miocene time, and is known for its wealth of vertebrate fossils.

[9][10] During the Pleistocene, the top of the Cypress Hills was not overridden by the Laurentide Ice Sheet and remained unglaciated.

As the ice sheet paused periodically during its final retreat, a series of morainal ridges of glacial till built up around the hills.

[14] Due to their higher elevation, the upper slopes and summit of the Cypress Hills experience cooler temperatures and greater rainfall than the surrounding semi-arid plains,[15] and they support a flora and fauna that is much like that of the mountains south of the Canada–United States border in Montana and Wyoming.

[16] The north-facing slopes and some of the valleys host forests of aspen, lodgepole pine, and white spruce.

[15] Case studies have detected vegetation changes through woody plant encroachment, with an annual increase of shrub cover of 1 per cent.

[18] Small mammals of the area include a wide variety of rodents, as well as shrews, bats, jackrabbits, skunks, mink, weasels, foxes, bobcats, Canada lynx, and others.

Historically the Cypress Hills were a meeting and conflict area for various Native Americans and Indigenous Canadians (First Nations) including the Cree, Assiniboine, Atsina, Blackfoot Confederacy, Saulteaux, Sioux, Crow, and others.

Summer days are mild to warm coupled with cool nights, while winters are cold and snowy with annual snowfall averaging 255.2 cm (100.5 in).