We all would agree the Upper Plains of North Dakota, with cold temperatures and harsh winds, would tax efforts to keep warm throughout the dark winter months. However, for people like the Mandan the area surrounding the Missouri, Heart, and Knife Rivers in North Dakota was home for centuries.

The Mandan were sedentary maize-based agriculturalists who lived in large earthen lodges. Towns like Huff contained 115 large homes with roughly a thousand residents, a larger ceremonial lodge, and all surrounded by large earthen and wood fortifications. Houses were organized along central foot paths. Lodges were fifty by thirty five feet, with an A-frame shaped roofs and frames made of wood. Exterior walls were banked with sod and earth to shield from harsh temperatures and extreme weather. The post and beam construction covered a sunken floor dug more than a foot into the earth. Four large center posts supported the crossbeams, and marked off the space for the central fire. A ring of smaller posts supported the outer circumference of lodge. The roof of logs did not meet at the very top, but rather remained open for light as well as ventilation. The walls of the lodge consisted of three layers: a lattice of willow twigs, then a thick thatch of grass, then a layer of sod. On the outside of the lodge a railing of sticks prevented the sliding of the sod, and would serve as handholds to allow for climbing atop the lodge to sun and socialize in warmer months. Each lodge had a shielded entryway with a windscreen. The earthen structure blended with the landscape, mimicking Mandan cosmology where "the world was an earth lodge supported by four posts" (Bear on the Flat, quoted in Fenn).

Since domestic spaces were the domain of women in Mandan culture, women constructed and maintained these lodges. Modern reconstructions mimicking traditional techniques highlight the labor intensive nature of lodge construction and the skill required to make a comfortable home. In this matrilenial culture men would move into their wife's lodge belonging to the maternal clan. Inside the lodge the further point, away from the door, was reserved for sacred space. The windscreen at the entryway prevented drafts, and individual family spaces were organized around the large central fire. Early European arrivals found lodges a welcome sanctuary from the cold, though admittedly a little smoky. Lewis and Clark survived the winter of 1804 thanks to the hospitality of the Mandan, and it was here they met Sakakawea/Sacagawea, a Shoshone abducted by Hidatsa raiders who eventually married Toussaint Charbonneau. After extensive interviews with Lewis and Clark describing the path westward, Sakakawea, infant in tow, would lead the Corps of Discovery toward her home in the spring of 1805.

For more info on the Mandan I highly recommend Fenn's Encounters at the Heart of the World: A History of the Mandan People, which I have used heavily in writing this answer.